23 results on '"Katschke KJ Jr"'
Search Results
2. Development of a therapeutic anti-HtrA1 antibody and the identification of DKK3 as a pharmacodynamic biomarker in geographic atrophy.
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Tom I, Pham VC, Katschke KJ Jr, Li W, Liang WC, Gutierrez J, Ah Young A, Figueroa I, Eshghi ST, Lee CV, Kanodia J, Snipas SJ, Salvesen GS, Lai P, Honigberg L, van Lookeren Campagne M, Kirchhofer D, Baruch A, and Lill JR
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- Adaptor Proteins, Signal Transducing isolation & purification, Aged, Animals, Antibodies, Anti-Idiotypic genetics, Antibodies, Anti-Idiotypic immunology, Biomarkers blood, Disease Progression, Female, Genetic Predisposition to Disease, Genotype, Geographic Atrophy blood, Geographic Atrophy genetics, Geographic Atrophy immunology, High-Temperature Requirement A Serine Peptidase 1 antagonists & inhibitors, Humans, Immunoglobulin Fab Fragments immunology, Immunoglobulin Fab Fragments pharmacology, Macular Degeneration blood, Macular Degeneration genetics, Macular Degeneration immunology, Male, Polymorphism, Single Nucleotide genetics, Proteome genetics, Proteome immunology, Rats, Retina drug effects, Retina immunology, Retina pathology, Small Molecule Libraries pharmacology, Adaptor Proteins, Signal Transducing genetics, Antibodies, Anti-Idiotypic pharmacology, Geographic Atrophy drug therapy, High-Temperature Requirement A Serine Peptidase 1 genetics, Macular Degeneration drug therapy
- Abstract
Genetic polymorphisms in the region of the trimeric serine hydrolase high-temperature requirement 1 ( HTRA1 ) are associated with increased risk of age-related macular degeneration (AMD) and disease progression, but the precise biological function of HtrA1 in the eye and its contribution to disease etiologies remain undefined. In this study, we have developed an HtrA1-blocking Fab fragment to test the therapeutic hypothesis that HtrA1 protease activity is involved in the progression of AMD. Next, we generated an activity-based small-molecule probe (ABP) to track target engagement in vivo. In addition, we used N-terminomic proteomic profiling in preclinical models to elucidate the in vivo repertoire of HtrA1-specific substrates, and identified substrates that can serve as robust pharmacodynamic biomarkers of HtrA1 activity. One of these HtrA1 substrates, Dickkopf-related protein 3 (DKK3), was successfully used as a biomarker to demonstrate the inhibition of HtrA1 activity in patients with AMD who were treated with the HtrA1-blocking Fab fragment. This pharmacodynamic biomarker provides important information on HtrA1 activity and pharmacological inhibition within the ocular compartment., Competing Interests: Competing interest statement: I.T., V.C.P., K.J.K., W.L., W.-C.L., J.G., A.A.Y., I.F., S.T.E., C.V.L., J.K., P.L., D.K., L.H., M.v.L.C., D.K., A.B., and J.R.L. were employees of Genentech, Inc. during performance of this work., (Copyright © 2020 the Author(s). Published by PNAS.)
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- 2020
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3. Integration of eQTL and a Single-Cell Atlas in the Human Eye Identifies Causal Genes for Age-Related Macular Degeneration.
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Orozco LD, Chen HH, Cox C, Katschke KJ Jr, Arceo R, Espiritu C, Caplazi P, Nghiem SS, Chen YJ, Modrusan Z, Dressen A, Goldstein LD, Clarke C, Bhangale T, Yaspan B, Jeanne M, Townsend MJ, van Lookeren Campagne M, and Hackney JA
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- Aged, Aged, 80 and over, Alleles, Choroid metabolism, Databases, Genetic, Female, Genome-Wide Association Study, Humans, Macular Degeneration genetics, Male, Middle Aged, Polymorphism, Single Nucleotide, Quantitative Trait Loci, RNA-Seq, Risk Factors, Single-Cell Analysis, TRPM Cation Channels genetics, TRPM Cation Channels metabolism, Tetraspanins genetics, Tetraspanins metabolism, Transcriptome genetics, Disease Susceptibility metabolism, Gene Expression Regulation genetics, Macular Degeneration metabolism, Retinal Pigment Epithelium metabolism
- Abstract
Age-related macular degeneration (AMD) is a leading cause of vision loss. To better understand disease pathogenesis and identify causal genes in GWAS loci for AMD risk, we present a comprehensive database of human retina and retinal pigment epithelium (RPE). Our database comprises macular and non-macular RNA sequencing (RNA-seq) profiles from 129 donors, a genome-wide expression quantitative trait loci (eQTL) dataset that includes macula-specific retina and RPE/choroid, and single-nucleus RNA-seq (NucSeq) from human retina and RPE with subtype resolution from more than 100,000 cells. Using NucSeq, we find enriched expression of AMD candidate genes in RPE cells. We identify 15 putative causal genes for AMD on the basis of co-localization of genetic association signals for AMD risk and eye eQTL, including the genes TSPAN10 and TRPM1. These results demonstrate the value of our human eye database for elucidating genetic pathways and potential therapeutic targets for ocular diseases., Competing Interests: Declaration of Interests L.D.O., H.-H.C., C. Cox, K.J.K., R.A., C.E., P.C., S.S.N., Y.-J.C., Z.M., A.D., L.D.G., C. Clarke, T.B., B.Y., M.J., M.J.T., M.v.L.C., and J.A.H. were employees of Genentech at the time these studies were carried out., (Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reserved.)
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- 2020
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4. Publisher Correction: Classical and alternative complement activation on photoreceptor outer segments drives monocyte-dependent retinal atrophy.
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Katschke KJ Jr, Xi H, Cox C, Truong T, Malato Y, Lee WP, McKenzie B, Arceo R, Tao J, Rangell L, Reichelt M, Diehl L, Elstrott J, Weimer RM, and van Lookeren Campagne M
- Abstract
A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.
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- 2018
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5. Prevention of Fatal C3 Glomerulopathy by Recombinant Complement Receptor of the Ig Superfamily.
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Wang X, Van Lookeren Campagne M, Katschke KJ Jr, Gullipalli D, Miwa T, Ueda Y, Wang Y, Palmer M, Xing G, and Song WC
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- Analysis of Variance, Animals, Biopsy, Needle, Blotting, Western, Complement Activation, Complement Factor B immunology, Complement Factor B metabolism, Disease Models, Animal, Glomerulonephritis, IGA pathology, Immunohistochemistry, Kidney Function Tests, Mice, Mice, Inbred C57BL, Random Allocation, Receptors, Complement metabolism, Survival Rate, Complement C3 antagonists & inhibitors, Complement C3 genetics, Glomerulonephritis, IGA genetics, Glomerulonephritis, IGA prevention & control, Guanine Nucleotide-Releasing Factor 2 genetics, Receptors, Complement genetics
- Abstract
Background C3 glomerulopathy (C3G) is a life-threatening kidney disease caused by dysregulation of the alternative pathway of complement (AP) activation. No approved specific therapy is available for C3G, although an anti-C5 mAb has been used off-label in some patients with C3G, with mixed results. Thus, there is an unmet medical need to develop other inhibitors of complement for C3G. Methods We used a murine model of lethal C3G to test the potential efficacy of an Fc fusion protein of complement receptor of the Ig superfamily (CRIg-Fc) in the treatment of C3G. CRIg-Fc binds C3b and inhibits C3 and C5 convertases of the AP. Mice with mutations in the factor H and properdin genes (FH
m/m P-/- ) develop early-onset C3G, with AP consumption, high proteinuria, and lethal crescentic GN. Results Treatment of FHm/m P-/- mice with CRIg-Fc, but not a control IgG, inhibited AP activation and diminished the consumption of plasma C3, factor B, and C5. CRIg-Fc-treated FHm/m P-/- mice also had significantly improved survival and reduced proteinuria, hematuria, BUN, glomerular C3 fragment, C9 and fibrin deposition, and GN pathology scores. Conclusions Therapeutics developed on the basis of the mechanism of action of soluble CRIg may be effective for the treatment of C3G and should be explored clinically., (Copyright © 2018 by the American Society of Nephrology.)- Published
- 2018
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6. Classical and alternative complement activation on photoreceptor outer segments drives monocyte-dependent retinal atrophy.
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Katschke KJ Jr, Xi H, Cox C, Truong T, Malato Y, Lee WP, McKenzie B, Arceo R, Tao J, Rangell L, Reichelt M, Diehl L, Elstrott J, Weimer RM, and van Lookeren Campagne M
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- Animals, Atrophy pathology, Complement Activation physiology, Complement C3 genetics, Complement C3 physiology, Complement C4 genetics, Complement C4 physiology, Geographic Atrophy genetics, Humans, Macular Degeneration physiopathology, Mice, Mice, Inbred C57BL, Mice, Knockout, Monocytes metabolism, Photoreceptor Cells metabolism, Retina metabolism, Retinal Degeneration pathology, Retinal Pigment Epithelium metabolism, Complement Activation genetics, Geographic Atrophy physiopathology, Retinal Rod Photoreceptor Cells metabolism
- Abstract
Geographic atrophy (GA), the advanced form of dry age-related macular degeneration (AMD), is characterized by progressive loss of retinal pigment epithelium cells and photoreceptors in the setting of characteristic extracellular deposits and remains a serious unmet medical need. While genetic predisposition to AMD is dominated by polymorphisms in complement genes, it remains unclear how complement activation contributes to retinal atrophy. Here we demonstrate that complement is activated on photoreceptor outer segments (POS) in the retina peripheral to atrophic lesions associated with GA. When exposed to human serum following outer blood-retinal barrier breakdown, POS act as potent activators of the classical and alternative complement pathway. In mouse models of retinal degeneration, classical and alternative pathway complement activation on photoreceptors contributed to the loss of photoreceptor function. This was dependent on C5a-mediated recruitment of peripheral blood monocytes but independent of resident microglia. Genetic or pharmacologic inhibition of both classical and alternative complement C3 and C5 convertases was required to reduce progressive degeneration of photoreceptor rods and cones. Our study implicates systemic classical and alternative complement proteins and peripheral blood monocytes as critical effectors of localized retinal degeneration with potential relevance for the contribution of complement activation to GA.
- Published
- 2018
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7. IL-33 amplifies an innate immune response in the degenerating retina.
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Xi H, Katschke KJ Jr, Li Y, Truong T, Lee WP, Diehl L, Rangell L, Tao J, Arceo R, Eastham-Anderson J, Hackney JA, Iglesias A, Cote-Sierra J, Elstrott J, Weimer RM, and van Lookeren Campagne M
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- Aged, Aged, 80 and over, Animals, Case-Control Studies, Cell Nucleus immunology, Cytokines metabolism, Ependymoglial Cells immunology, Ependymoglial Cells pathology, Female, Humans, In Vitro Techniques, Interleukin-1 Receptor-Like 1 Protein, Interleukin-33 chemistry, Interleukin-33 deficiency, Interleukin-33 genetics, Macula Lutea immunology, Macula Lutea pathology, Macular Degeneration genetics, Macular Degeneration pathology, Male, Mice, Mice, Inbred BALB C, Mice, Inbred C57BL, Mice, Knockout, Protein Processing, Post-Translational, Rats, Receptors, Cell Surface genetics, Receptors, Cell Surface metabolism, Receptors, Interleukin deficiency, Receptors, Interleukin genetics, Receptors, Interleukin metabolism, Retinal Pigment Epithelium immunology, Retinal Pigment Epithelium pathology, Immunity, Innate, Interleukin-33 metabolism, Macular Degeneration immunology
- Abstract
Age-related macular degeneration (AMD), a leading cause of vision impairment in the ageing population, is characterized by irreversible loss of retinal pigment epithelial (RPE) cells and photoreceptors and can be associated with choroidal neovascularization. Mononuclear phagocytes are often present in AMD lesions, but the processes that direct myeloid cell recruitment remain unclear. Here, we identify IL-33 as a key regulator of inflammation and photoreceptor degeneration after retina stress or injury. IL-33(+) Müller cells were more abundant and IL-33 cytokine was elevated in advanced AMD cases compared with age-matched controls with no AMD. In rodents, retina stress resulted in release of bioactive IL-33 that in turn increased inflammatory chemokine and cytokine expression in activated Müller cells. Deletion of ST2, the IL-33 receptor α chain, or treatment with a soluble IL-33 decoy receptor significantly reduced release of inflammatory mediators from Müller cells, inhibited accumulation of mononuclear phagocytes in the outer retina, and protected photoreceptor rods and cones after a retina insult. This study demonstrates a central role for IL-33 in regulating mononuclear phagocyte recruitment to the photoreceptor layer and positions IL-33 signaling as a potential therapeutic target in macular degenerative diseases., (© 2016 Xi et al.)
- Published
- 2016
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8. CRIg mediates early Kupffer cell responses to adenovirus.
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He JQ, Katschke KJ Jr, Gribling P, Suto E, Lee WP, Diehl L, Eastham-Anderson J, Ponakala A, Komuves L, Egen JG, and van Lookeren Campagne M
- Subjects
- Adenoviridae physiology, Adenoviridae Infections immunology, Adenoviridae Infections virology, Animals, Cell Death, Complement Activation, Flow Cytometry, Immunohistochemistry, Mice, Mice, Knockout, Microscopy, Confocal, Adenoviridae immunology, Kupffer Cells cytology, Kupffer Cells immunology, Receptors, Complement immunology, Receptors, Complement metabolism
- Abstract
Whereas adenoviral vectors are known to activate the complement cascade, leading to fixation of C3 proteins to the viral capsid, the consequences of this activation for viral clearance from the circulation are not known. Liver KCs, the macrophage population responsible for early uptake and elimination of many blood-borne pathogens, express CRIg, a complement receptor for C3 proteins. Here, we find that CRIg is important for the early elimination of C3-coated adenoviral vectors from the sinusoidal bloodstream by KCs. We further demonstrate that by acting as a critical receptor for adenovirus phagocytosis, CRIg plays an important role in regulating virus-induced KC death and depletion of these cells from the liver sinusoidal lumen. Our study thus identifies a critical pathway regulating KC function and survival in response to systemic viral infection.
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- 2013
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9. Activation of the alternative complement pathway in vitreous is controlled by genetics in age-related macular degeneration.
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Loyet KM, Deforge LE, Katschke KJ Jr, Diehl L, Graham RR, Pao L, Sturgeon L, Lewin-Koh SC, Hollyfield JG, and van Lookeren Campagne M
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- Aged, Aged, 80 and over, Bruch Membrane metabolism, Choroid metabolism, Complement Activation, Complement C3 genetics, Complement Factor B genetics, Complement Factor D genetics, Complement Factor H genetics, Disease Progression, Enzyme-Linked Immunosorbent Assay, Female, Genotype, Humans, Immunohistochemistry, Macular Degeneration metabolism, Male, Middle Aged, Polymerase Chain Reaction, Polymorphism, Single Nucleotide, Tissue Donors, Complement C3 metabolism, Complement Factor B metabolism, Complement Factor D metabolism, Complement Pathway, Alternative genetics, Macular Degeneration genetics, Vitreous Body metabolism
- Abstract
Purpose: To determine if the progression of age-related macular degeneration (AMD) is associated with complement activation in the eye., Methods: Immunohistochemistry and ELISAs were used to determine the distribution, concentration, and activation of the alternative pathway complement proteases factor B (FB) and factor D (FD) and the central complement protein C3 in genotyped human postmortem donor eyes graded as having no or minimal drusen (category 1; controls), large drusen (category 3), and large drusen with advanced AMD (category 4)., Results: C3, FB, and FD were present in vitreous and Bruch's membrane choroid (BM/C) interface of the macula of eyes in all tested AMD severity categories (n = 100). C3, FB, and FD were predominantly located to the choroidal vasculature and Bruch's membrane and, together with the serum proteins transferrin and albumin, elevated in BM/C extracts of category 4 eyes (n = 23) compared with category 1 eyes (n = 24). A significant increase in FB activation was found only in vitreous of category 4 eyes (n = 23) compared with category 1 eyes (n = 25). Genetic variants of complement factor H (CFH), C3, C2, and FB associated with increased risk of AMD were correlated with alternative pathway complement activation in vitreous, but not with complement proteins in BM/C protein extracts., Conclusions: Increased activation of the alternative complement pathway in vitreous was controlled by disease stage and genetic variation in the complement pathway, supporting a role for complement activation in AMD disease pathogenesis.
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- 2012
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10. Inhibiting alternative pathway complement activation by targeting the factor D exosite.
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Katschke KJ Jr, Wu P, Ganesan R, Kelley RF, Mathieu MA, Hass PE, Murray J, Kirchhofer D, Wiesmann C, and van Lookeren Campagne M
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- Animals, Antibodies genetics, Antibodies metabolism, Antibody Specificity, Complement C3-C5 Convertases metabolism, Complement C3b metabolism, Complement Factor D genetics, Crystallography, Esters metabolism, Humans, Hybridomas, Immunoglobulin Fab Fragments immunology, Immunoglobulin Fab Fragments metabolism, Macaca fascicularis, Mice, Protein Binding immunology, Protein Structure, Tertiary, Recombinant Proteins genetics, Recombinant Proteins immunology, Recombinant Proteins metabolism, Antibodies immunology, Complement Factor D chemistry, Complement Factor D immunology, Complement Pathway, Alternative immunology
- Abstract
By virtue of its amplifying property, the alternative complement pathway has been implicated in a number of inflammatory diseases and constitutes an attractive therapeutic target. An anti-factor D Fab fragment (AFD) was generated to inhibit the alternative complement pathway in advanced dry age-related macular degeneration. AFD potently prevented factor D (FD)-mediated proteolytic activation of its macromolecular substrate C3bB, but not proteolysis of a small synthetic substrate, indicating that AFD did not block access of the substrate to the catalytic site. The crystal structures of AFD in complex with human and cynomolgus FD (at 2.4 and 2.3 Å, respectively) revealed the molecular details of the inhibitory mechanism. The structures show that the AFD-binding site includes surface loops of FD that form part of the FD exosite. Thus, AFD inhibits FD proteolytic function by interfering with macromolecular substrate access rather than by inhibiting FD catalysis, providing the molecular basis of AFD-mediated inhibition of a rate-limiting step in the alternative complement pathway.
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- 2012
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11. Negative regulation of autoimmune demyelination by the inhibitory receptor CLM-1.
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Xi H, Katschke KJ Jr, Helmy KY, Wark PA, Kljavin N, Clark H, Eastham-Anderson J, Shek T, Roose-Girma M, Ghilardi N, and van Lookeren Campagne M
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- Animals, Cytokines genetics, Cytokines immunology, Encephalomyelitis, Autoimmune, Experimental chemically induced, Encephalomyelitis, Autoimmune, Experimental genetics, Encephalomyelitis, Autoimmune, Experimental pathology, Glycoproteins adverse effects, Glycoproteins pharmacology, Inflammation chemically induced, Inflammation genetics, Inflammation immunology, Inflammation Mediators metabolism, Mice, Mice, Knockout, Multiple Sclerosis chemically induced, Multiple Sclerosis genetics, Multiple Sclerosis pathology, Myelin-Oligodendrocyte Glycoprotein, Myeloid Cells pathology, Nitric Oxide genetics, Nitric Oxide immunology, Peptide Fragments adverse effects, Peptide Fragments pharmacology, Receptors, Immunologic genetics, Encephalomyelitis, Autoimmune, Experimental immunology, Multiple Sclerosis immunology, Myeloid Cells immunology, Receptors, Immunologic immunology
- Abstract
Multiple sclerosis and its preclinical model, experimental autoimmune encephalomyelitis, are marked by perivascular inflammation and demyelination. Myeloid cells, derived from circulating progenitors, are a prominent component of the inflammatory infiltrate and are believed to directly contribute to demyelination and axonal damage. How the cytotoxic activity of these myeloid cells is regulated is poorly understood. We identify CMRF-35-like molecule-1 (CLM-1) as a negative regulator of autoimmune demyelination. CLM-1 is expressed on inflammatory myeloid cells present in demyelinating areas of the spinal cord after immunization of mice with MOG35-55 (myelin oligodendrocyte glycoprotein) peptide. Absence of CLM-1 resulted in significantly increased nitric oxide and proinflammatory cytokine production, along with increased demyelination and worsened clinical scores, whereas T cell responses in the periphery or in the spinal cord remained unaffected. This study thus identifies CLM-1 as a negative regulator of myeloid effector cells in autoimmune demyelination.
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- 2010
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12. Structural and functional analysis of a C3b-specific antibody that selectively inhibits the alternative pathway of complement.
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Katschke KJ Jr, Stawicki S, Yin J, Steffek M, Xi H, Sturgeon L, Hass PE, Loyet KM, Deforge L, Wu Y, van Lookeren Campagne M, and Wiesmann C
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- Animals, Complement C3 Convertase, Alternative Pathway metabolism, Complement C3b chemistry, Complement C3b genetics, Complement C3b metabolism, Complement C5 Convertase, Alternative Pathway metabolism, Crystallography, X-Ray, Enzyme Inhibitors chemistry, Enzyme Inhibitors metabolism, Enzyme Stability, Humans, Macaca mulatta, Models, Molecular, Molecular Sequence Data, Peptide Library, Peptides, Cyclic chemistry, Peptides, Cyclic metabolism, Receptors, Complement 3b chemistry, Receptors, Complement 3b metabolism, Antibodies chemistry, Antibodies metabolism, Complement C3b immunology, Complement Pathway, Alternative physiology, Immunoglobulin Fab Fragments chemistry, Immunoglobulin Fab Fragments metabolism, Protein Conformation
- Abstract
Amplification of the complement cascade through the alternative pathway can lead to excessive inflammation. Targeting C3b, a component central to the alternative pathway of complement, provides a powerful approach to inhibit complement-mediated immune responses and tissue injury. In the present study, phage display technology was employed to generate an antibody that selectively recognizes C3b but not the non-activated molecule C3. The crystal structure of C3b in complex with a Fab fragment of this antibody (S77) illustrates the structural basis for this selectivity. Cleavage of C3 to C3b results in a plethora of structural changes within C3, including the rearrangement of macroglobulin domain 6 enabling binding of S77 to the adjacent macroglobulin domain 7 domain. S77 blocks binding of factor B to C3b inhibiting the first step in the formation of the alternative pathway C3 convertase. In addition, S77 inhibits C5 binding to C3b. This results in significantly reduced formations of anaphylatoxins and membrane-attack complexes. This study for the first time demonstrates the structural basis for complement inhibition by a C3b-selective antibody and provides insights into the molecular mechanisms of alternative pathway complement activation.
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- 2009
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13. Complement receptor of the Ig superfamily enhances complement-mediated phagocytosis in a subpopulation of tissue resident macrophages.
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Gorgani NN, He JQ, Katschke KJ Jr, Helmy KY, Xi H, Steffek M, Hass PE, and van Lookeren Campagne M
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- Animals, CD18 Antigens immunology, Calcium immunology, Gene Expression Regulation immunology, Ligands, Magnesium immunology, Mice, Mice, Inbred AKR, Mice, Knockout, Receptors, Complement agonists, Complement C3 immunology, Macrophages immunology, Phagocytosis immunology, Receptors, Complement immunology
- Abstract
An important function of the complement cascade is to coat self and foreign particles with C3-proteins that serve as ligands for phagocytic receptors. Although tissue resident macrophages play an important role in complement-mediated clearance, the receptors coordinating this process have not been well characterized. In the present study, we identified a subpopulation of resident peritoneal macrophages characterized by high expression of complement receptor of the Ig superfamily (CRIg), a recently discovered complement C3 receptor. Macrophages expressing CRIg showed significantly increased binding and subsequent internalization of complement-opsonized particles compared with CRIg negative macrophages. CRIg internalized monovalent ligands and was able to bind complement-opsonized targets in the absence of Ca(2+) and Mg(2+), which differs from the beta(2)-integrin CR3 that requires divalent cations and polyvalent ligands for activation of the receptor. Although CRIg dominated in immediate binding of complement-coated particles, CRIg and CR3 contributed independently to subsequent particle phagocytosis. CRIg thus identifies a subset of tissue resident macrophages capable of increased phagocytosis of complement C3-coated particles, a function critical for immune clearance.
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- 2008
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14. A novel inhibitor of the alternative pathway of complement reverses inflammation and bone destruction in experimental arthritis.
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Katschke KJ Jr, Helmy KY, Steffek M, Xi H, Yin J, Lee WP, Gribling P, Barck KH, Carano RA, Taylor RE, Rangell L, Diehl L, Hass PE, Wiesmann C, and van Lookeren Campagne M
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- Animals, Arthritis, Experimental complications, Bone Resorption etiology, Complement Inactivating Agents, Crystallization, Enzyme-Linked Immunosorbent Assay, Humans, Immunohistochemistry, Mice, Receptors, Complement chemistry, Arthritis, Experimental drug therapy, Bone Resorption drug therapy, Models, Molecular, Receptors, Complement genetics
- Abstract
Complement is an important component of the innate and adaptive immune response, yet complement split products generated through activation of each of the three complement pathways (classical, alternative, and lectin) can cause inflammation and tissue destruction. Previous studies have shown that complement activation through the alternative, but not classical, pathway is required to initiate antibody-induced arthritis in mice, but it is unclear if the alternative pathway (AP) plays a role in established disease. Previously, we have shown that human complement receptor of the immunoglobulin superfamily (CRIg) is a selective inhibitor of the AP of complement. Here, we present the crystal structure of murine CRIg and, using mutants, provide evidence that the structural requirements for inhibition of the AP are conserved in human and mouse. A soluble form of CRIg reversed inflammation and bone loss in two experimental models of arthritis by inhibiting the AP of complement in the joint. Our data indicate that the AP of complement is not only required for disease induction, but also disease progression. The extracellular domain of CRIg thus provides a novel tool to study the effects of inhibiting the AP of complement in established disease and constitutes a promising therapeutic with selectivity for a single complement pathway.
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- 2007
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15. CRIg: a macrophage complement receptor required for phagocytosis of circulating pathogens.
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Helmy KY, Katschke KJ Jr, Gorgani NN, Kljavin NM, Elliott JM, Diehl L, Scales SJ, Ghilardi N, and van Lookeren Campagne M
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- Animals, Complement C3 immunology, Complement C3b immunology, Endosomes metabolism, Humans, Kupffer Cells cytology, Kupffer Cells immunology, Listeriosis immunology, Macrophages cytology, Mice, Opsonin Proteins metabolism, Peptide Fragments immunology, Protein Binding, Receptors, Complement genetics, Receptors, Complement 3b, Macrophages immunology, Phagocytosis physiology, Receptors, Complement immunology
- Abstract
The complement system serves an important role in clearance of pathogens, immune complexes, and apoptotic cells present in the circulation. Complement fragments deposited on the particle surface serve as targets for complement receptors present on phagocytic cells. Although Kupffer cells, the liver resident macrophages, play a dominant role in clearing particles in circulation, complement receptors involved in this process have yet to be identified. Here we report the identification and characterization of a Complement Receptor of the Immunoglobulin superfamily, CRIg, that binds complement fragments C3b and iC3b. CRIg expression on Kupffer cells is required for efficient binding and phagocytosis of complement C3-opsonized particles. In turn, Kupffer cells from CRIg-deficient mice are unable to efficiently clear C3-opsonized pathogens in the circulation, resulting in increased infection and mortality of the host. CRIg therefore represents a dominant component of the phagocytic system responsible for rapid clearance of C3-opsonized particles from the circulation.
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- 2006
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16. A novel function for a glucose analog of blood group H antigen as a mediator of leukocyte-endothelial adhesion via intracellular adhesion molecule 1.
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Zhu K, Amin MA, Kim MJ, Katschke KJ Jr, Park CC, and Koch AE
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- Active Transport, Cell Nucleus, Blotting, Western, Cell Adhesion, Cell Nucleus metabolism, Cytoplasm metabolism, Dose-Response Relationship, Drug, Enzyme Inhibitors pharmacology, Enzyme-Linked Immunosorbent Assay, Genes, Reporter, HL-60 Cells, Humans, Inflammation, Janus Kinase 2, Ligands, Luciferases metabolism, Microcirculation, Microscopy, Fluorescence, Models, Biological, Phosphatidylinositol 3-Kinases metabolism, Precipitin Tests, Protein Binding, Protein Transport, Protein-Tyrosine Kinases metabolism, Signal Transduction, Time Factors, Up-Regulation, ABO Blood-Group System immunology, Endothelium, Vascular cytology, Glucose chemistry, Intercellular Adhesion Molecule-1 metabolism, Leukocytes cytology, Proto-Oncogene Proteins
- Abstract
The 4A11 antigen is a unique cytokine-inducible antigen up-regulated on rheumatoid arthritis synovial endothelium compared with normal endothelium. In soluble form, this antigen, Lewisy-6/H-5-2 (Ley/H), or its glucose analog, 2-fucosyllactose (H-2g), mediates angiogenesis. The Ley/H antigen is structurally related to the soluble E-selectin ligand, sialyl Lewisx, and is selectively expressed in skin, lymphoid organs, thymus, and synovium, suggesting that it may be important in leukocyte homing or adhesion. In the present study, we used H-2g as a functional substitute to demonstrate a novel property for Ley/H antigen in inducing leukocyte-endothelial adhesion. H-2g significantly enhanced the expression of human dermal microvascular endothelial cells (HMVECs) intercellular adhesion molecule-1 (ICAM-1), but not vascular cell adhesion molecule-1, E-selectin, and P-selectin. Immunoprecipitation and Western blotting showed glycolipids Ley-6, H-5-2, or the glucose analog H-2g quickly activated human microvascular endothelial cell line-1 (HMEC-1) Janus kinase 2 (JAK2) and that the JAK2 inhibitor, AG-490, completely inhibited HMVEC ICAM-1 expression and HL-60 adhesion to HMEC-1s. Use of a JAK/signal transducer and activator of transcription (STAT) profiling system confirmed that H-2g selectively activated STAT3 but not STAT1 and STAT2. AG-490 inhibited H-2g-induced Erk1/2 and PI3K-Akt activation, suggesting that JAK2 is upstream of the Erk1/2 and PI3K-Akt pathways. Furthermore, the JAK2 inhibitor AG-490, the Erk1/2 inhibitor PD98059, or the phosphatidylinositol 3-kinase inhibitor LY294002 or antisense oligodeoxynucleotides directed against JAK2, Erk1/2, or phosphatidylinositol 3-kinase blocked H-2g-induced HMVEC ICAM-1 expression and HL-60 adhesion to HMEC-1s. Hence, H-2g signals through JAK2 and its downstream signal transducers STAT3, Erk1/2, and phosphatidylinositol 3-kinase result in ICAM-1 expression and cell adhesion. Potential treatment strategies through the inhibition of JAK-dependent pathways to target H-2g signals may provide a useful approach in inflammation-driven diseases like rheumatoid arthritis.
- Published
- 2003
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17. Interleukin-13 gene therapy reduces inflammation, vascularization, and bony destruction in rat adjuvant-induced arthritis.
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Woods JM, Amin MA, Katschke KJ Jr, Volin MV, Ruth JH, Connors MA, Woodruff DC, Kurata H, Arai K, Haines GK 3rd, Kumar P, and Koch AE
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- Adenoviridae, Animals, Ankle pathology, Ankle physiopathology, Arthritis, Experimental immunology, Arthritis, Experimental pathology, Bone and Bones drug effects, Bone and Bones pathology, Disease Models, Animal, Fibroblasts, Inflammation drug therapy, Inflammation genetics, Inflammation immunology, Interleukin-13 administration & dosage, Mycobacterium, Rats, Arthritis, Experimental drug therapy, Genetic Therapy, Interleukin-13 genetics, Interleukin-13 therapeutic use
- Abstract
Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease characterized by synovial pannus formation, leukocyte infiltration, and angiogenesis. Adenoviral production of interleukin-13 (IL-13) reduces levels of proinflammatory mediators in an explant model of RA synovial tissue in vitro. To assess this approach in an animal model of arthritis, we compared intra-articular injections of an adenovirus producing rat IL-13 (AxCArIL-13), a control virus, and rat ankles receiving phosphate-buffered saline (PBS) in rat adjuvant-induced arthritis (AIA). We demonstrate that IL-13 levels are normally low in ankles throughout the course of rat AIA. We show that administration of AxCArIL-13 before arthritis onset significantly reduces ankle circumference, paw volume, bony destruction, the number of polymorphonuclear cells (PMNs), the quantity of blood vessels, and levels of monocyte chemoattractant protein (MCP)-1 in ankles. When administered as a treatment to inflamed ankles, AxCArIL-13 decreases articular index scores, paw volumes, bony destruction, vascularization, tumor necrosis factor-alpha (TNF-alpha) levels, and the quantity of monocytes, lymphocytes, and PMNs. Thus, increasing IL-13 levels significantly ameliorates the course of rat AIA, suggesting that similar strategies for the treatment of human RA are worthy of further study.
- Published
- 2002
- Full Text
- View/download PDF
18. Selective lymphocyte chemokine receptor expression in the rheumatoid joint.
- Author
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Ruth JH, Rottman JB, Katschke KJ Jr, Qin S, Wu L, LaRosa G, Ponath P, Pope RM, and Koch AE
- Subjects
- CD3 Complex analysis, CD4-Positive T-Lymphocytes chemistry, CD4-Positive T-Lymphocytes immunology, CD8-Positive T-Lymphocytes chemistry, CD8-Positive T-Lymphocytes immunology, CX3C Chemokine Receptor 1, Flow Cytometry, Fluorescent Antibody Technique, Humans, Immunologic Memory immunology, Joints chemistry, Receptors, CCR4, Receptors, CCR5 analysis, Receptors, CCR5 immunology, Receptors, CXCR3, Receptors, Chemokine analysis, Receptors, Cytokine analysis, Receptors, Cytokine immunology, Receptors, HIV analysis, Receptors, HIV immunology, Synovial Fluid chemistry, Arthritis, Rheumatoid immunology, Joints immunology, Receptors, Chemokine immunology, Synovial Fluid immunology
- Abstract
Objective: In patients with rheumatoid arthritis (RA), chemokines and their receptors are important for lymphocyte trafficking into the inflamed joint. This study was undertaken to characterize the expression of chemokine receptors CCR1, CCR2, CCR3, CCR4, CCR5, CCR6, CXCR3, and CX3CR1 in normal (NL) peripheral blood (PB), RA PB, and RA synovial fluid (SF)., Methods: Using flow cytometry, immunohistochemistry, and 2-color immunofluorescence, we defined the expression of chemokine receptors on CD3+ T lymphocytes in RA synovial tissue (ST), RA SF, RA PB, and NL PB., Results: The percentage of CD3+ lymphocytes expressing CCR2, CCR4, CCR5, and CX3CR1 was significantly elevated in RA PB compared with that in NL PB, while the percentage of CD3+ lymphocytes expressing CCR5 was significantly enhanced in RA SF compared with that in NL and RA PB. In contrast, similar percentages of CD3+ lymphocytes in NL PB, RA PB, and RA SF expressed CCR6 and CXCR3. Immunohistochemistry of RA ST showed lymphocyte expression of CCR4, and 2-color immunofluorescence staining revealed RA ST CD3+ lymphocytes intensely immunoreactive for CXCR3, suggesting that these 2 receptors may be particularly important for CD3+ lymphocyte trafficking to the inflamed joint. In comparisons of chemokine receptor expression on naive (CD45RA+) and memory (CD45RO+) CD3+ lymphocytes, there were greater percentages of memory CD3+/CD4+ lymphocytes expressing CCR4, CCR5, and CXCR3 than naive CD3+/CD4+ lymphocytes in RA PB and RA SF, and greater percentages of memory CD3+/CD8+ lymphocytes expressing CCR4, CCR5, and CXCR3 than naive CD3+/CD8+ lymphocytes in RA SF, suggesting receptor up-regulation upon lymphocyte activation. In contrast, percentages of CD3+/CD8+ memory lymphocytes expressing CX3CR1 were significantly less than percentages of naive CD3+/CD8+ lymphocytes in RA PB, suggesting that this receptor may be down-regulated upon lymphocyte activation. A major difference between the RA PB and NL PB groups was significantly more CCR4+ memory leukocytes and memory CCR5+/ CD3+/CD8+ lymphocytes in RA PB than NL PB, further suggesting that these receptors may be particularly important for lymphocyte homing to the RA joint., Conclusion: These results identify CCR4, CCR5, CXCR3, and CX3CR1 as critical chemokine receptors in RA.
- Published
- 2001
- Full Text
- View/download PDF
19. Fractalkine, a novel chemokine in rheumatoid arthritis and in rat adjuvant-induced arthritis.
- Author
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Ruth JH, Volin MV, Haines GK 3rd, Woodruff DC, Katschke KJ Jr, Woods JM, Park CC, Morel JC, and Koch AE
- Subjects
- Adult, Animals, Arthritis, Experimental immunology, Arthritis, Rheumatoid immunology, CD3 Complex analysis, CX3C Chemokine Receptor 1, Chemokine CX3CL1, Chemokines, CX3C analysis, Chemotaxis, Leukocyte immunology, Enzyme-Linked Immunosorbent Assay, Female, Fibroblasts drug effects, Fibroblasts metabolism, Flow Cytometry, Gene Expression immunology, Humans, Interleukin-1 pharmacology, Kinetics, Lipopolysaccharide Receptors analysis, Membrane Proteins analysis, Monocytes chemistry, Monocytes cytology, Monocytes immunology, RNA, Messenger analysis, Rats, Rats, Inbred Lew, Receptors, Cytokine analysis, Receptors, HIV analysis, Solubility, Synovial Fluid immunology, Synovial Fluid metabolism, T-Lymphocytes chemistry, T-Lymphocytes immunology, Tarsus, Animal immunology, Tarsus, Animal metabolism, Tumor Necrosis Factor-alpha pharmacology, Up-Regulation immunology, Arthritis, Experimental metabolism, Arthritis, Rheumatoid metabolism, Chemokines, CX3C genetics, Membrane Proteins genetics, Receptors, Cytokine genetics, Receptors, HIV genetics
- Abstract
Objective: To examine the expression of the novel CX3C chemokine fractalkine (Fkn) and its receptor (CX3CR1) in rheumatoid arthritis (RA) and rat adjuvant-induced arthritis (AIA), a model of RA., Methods: Immunohistochemistry, flow cytometry, enzyme-linked immunosorbent assay (ELISA), reverse transcriptase-polymerase chain reaction (RT-PCR), and chemotaxis assays were used., Results: In rat AIA, synovial tissue (ST) macrophages, fibroblasts, endothelial cells, and dendritic cells were Fkn immunopositive, whereas lymphocytes did not significantly express Fkn. Significant staining for CX3CR1 was found in ST macrophages, fibroblasts, and dendritic cells, whereas only a small percentage of endothelial cells stained for CX3CR1 in rat AIA. We immunolocalized Fkn to RA ST macrophages, fibroblasts, endothelial cells, and dendritic cells. We also found intense ST macrophage and dendritic cell staining for CX3CR1 in RA ST. Flow cytometry analysis of RA synovial fluid (SF) and peripheral blood revealed a greater percentage of monocytes expressing Fkn and CX3CR1 compared with T cells. By ELISA, we found significantly elevated soluble Fkn (sFkn) levels in RA SF compared with SF from patients with osteoarthritis or other forms of arthritis. By RT-PCR, we found enhanced expression of Fkn and CX3CR1 mRNA on day 18 in rat AIA, a time of pronounced inflammation in the rat joint. Soluble Fkn-depleted RA SF showed significantly decreased chemotactic activity for monocytes compared with sham-depleted RA SF., Conclusion: These results indicate that Fkn and its receptor are both expressed in RA and in rat AIA, and that sFkn is up-regulated in RA SF. Furthermore, our data suggest a new role for Fkn in monocyte chemotaxis in the inflamed RA joint.
- Published
- 2001
- Full Text
- View/download PDF
20. Differential expression of chemokine receptors on peripheral blood, synovial fluid, and synovial tissue monocytes/macrophages in rheumatoid arthritis.
- Author
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Katschke KJ Jr, Rottman JB, Ruth JH, Qin S, Wu L, LaRosa G, Ponath P, Park CC, Pope RM, and Koch AE
- Subjects
- Adult, Chemokine CCL2 immunology, Chemokine CCL2 metabolism, Chemokine CCL5 immunology, Chemokine CCL5 metabolism, Female, Flow Cytometry, Humans, Macrophages immunology, Macrophages metabolism, Male, Monocytes immunology, Monocytes metabolism, Receptors, CCR6, Receptors, CXCR3, Receptors, CXCR4 biosynthesis, Receptors, CXCR4 immunology, Receptors, CXCR5, Receptors, Chemokine immunology, Receptors, Cytokine biosynthesis, Receptors, Cytokine immunology, Receptors, Interleukin-8A biosynthesis, Receptors, Interleukin-8A immunology, Receptors, Interleukin-8B biosynthesis, Receptors, Interleukin-8B immunology, Synovial Fluid cytology, Synovial Fluid immunology, Synovial Membrane cytology, Synovial Membrane immunology, Arthritis, Rheumatoid immunology, Arthritis, Rheumatoid metabolism, Receptors, Chemokine biosynthesis, Synovial Fluid metabolism, Synovial Membrane metabolism
- Abstract
Objective: Since it is likely that monocytes utilize chemokines to migrate to the rheumatoid arthritis (RA) joint, we investigated the expression of C-C chemokine receptors (CCR) 1-6 and C-X-C receptor 3 (CXCR3) in the peripheral blood (PB), synovial fluid (SF), and synovial tissue of patients with RA as well as in the PB of normal subjects., Methods: We compared chemokine receptor expression on CD14+ monocytes from normal PB, RA PB, and RA SF using 2-color flow cytometry. Correlations with patient clinical data were determined. Chemokine and receptor expression were investigated in RA synovial tissue by immunohistochemistry and 2-color immunofluorescence to identify CD68+ macrophages., Results: Most normal PB monocytes expressed CCR1 (87%) and CCR2 (84%), but not CCRs 3, 4, 5, or 6 or CXCR3. RA PB monocytes expressed CCR1 (56%) and CCR2 (76%), with significantly more expressing CCR3 (18%), CCR4 (38%), and CCR5 (17%) compared with normal PB monocytes. Significantly fewer SF monocytes from RA patients expressed CCR1 (17%), CCR2 (24%), and CCR4 (6%) while significantly more expressed CCR3 (35%) and CCR5 (47%) compared with RA and normal PB monocytes; CCR6 and CXCR3 were rarely detected. Clinically, the erythrocyte sedimentation rate was inversely correlated with the expression of CCR1 and CCR4 by RA PB, and CCR5 expression by RA SF was correlated with the SF white blood cell count. CCR1-, CCR2-, and CCR5-immunoreactive cells were found in RA synovial tissue and colocalized with CD68+ macrophages. RA synovial tissue RANTES (regulated upon activation, normally T cell expressed and secreted chemokine)- and monocyte chemoattractant protein 1-immunoreactive cells colocalized with CCR1 and CCR2, respectively, on serial sections. Macrophage inflammatory protein 1alpha (MIP-1alpha) was principally restricted to vascular endothelium, and MIP-1beta+ macrophages were found throughout the sections., Conclusion: Monocytes mainly express CCR1 and CCR2 in normal and RA PB, CCR3 and CCR5 in RA PB and RA SF, and CCR4 in RA PB. The differential expression of chemokine receptors suggests that certain receptors aid in monocyte recruitment from the circulation while others are important in monocyte retention in the joint.
- Published
- 2001
- Full Text
- View/download PDF
21. Reduction of inflammatory cytokines and prostaglandin E2 by IL-13 gene therapy in rheumatoid arthritis synovium.
- Author
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Woods JM, Katschke KJ Jr, Tokuhira M, Kurata H, Arai KI, Campbell PL, and Koch AE
- Subjects
- Adenoviridae genetics, Adenoviridae immunology, Adult, Arthritis, Rheumatoid genetics, Arthritis, Rheumatoid pathology, Chemokine CCL2 antagonists & inhibitors, Chemokine CCL4, Chemokine CCL5 metabolism, Chemokine CXCL1, Chemokine CXCL5, Chemokines, CXC antagonists & inhibitors, Chemokines, CXC metabolism, Chemotactic Factors antagonists & inhibitors, Chemotactic Factors metabolism, Culture Media, Conditioned metabolism, Cytokines biosynthesis, Dinoprostone biosynthesis, Female, Genetic Vectors immunology, Genetic Vectors pharmacology, Growth Substances metabolism, Humans, Hyaluronan Receptors metabolism, Intercellular Adhesion Molecule-1 metabolism, Interleukin-1 antagonists & inhibitors, Interleukin-1 metabolism, Interleukin-13 biosynthesis, Interleukin-13 physiology, Interleukin-8 antagonists & inhibitors, Interleukin-8 metabolism, Macrophage Inflammatory Proteins antagonists & inhibitors, Male, Middle Aged, Organ Culture Techniques, Recombinant Proteins pharmacology, Solubility, Synovial Membrane pathology, Synovial Membrane virology, Tumor Necrosis Factor-alpha antagonists & inhibitors, Tumor Necrosis Factor-alpha metabolism, Arthritis, Rheumatoid immunology, Arthritis, Rheumatoid therapy, Cytokines antagonists & inhibitors, Dinoprostone antagonists & inhibitors, Genetic Therapy, Intercellular Signaling Peptides and Proteins, Interleukin-13 genetics, Interleukin-8 analogs & derivatives, Synovial Membrane immunology, Synovial Membrane metabolism
- Abstract
The rheumatoid arthritis (RA) joint is characterized by an inflammatory synovial pannus which mediates tissue destruction. IL-13 is a cytokine that inhibits activated monocytes/macrophages from secreting a variety of proinflammatory molecules. The aim of this study was to examine whether gene therapy-delivered IL-13 could reduce the production of key proinflammatory mediators in RA synovial tissue (ST) explants. Adenoviral vectors encoding the genes for human IL-13 (AxCAIL-13) and bacterial beta-galactosidase were generated and examined for protein production. Vectors were used to infect RA ST explants and RA synovial fibroblasts, and conditioned medium (CM) was collected at various times for analysis by ELISA and competitive immunoassay. AxCAIL-13 decreased the production of RA ST explant proinflammatory IL-1beta by 85% after 24 h. Likewise, TNF-alpha levels were decreased by 82 and 75% whereas IL-8 levels were reduced 54 and 82% after 24 and 48 h, respectively, in RA ST explant CM. Monocyte chemotactic protein-1 concentrations were decreased by 88% after 72 h in RA ST explant CM. RA ST explant epithelial neutrophil-activating peptide-78 concentrations were decreased 85 and 94% whereas growth-related gene product-alpha levels were decreased by 77 and 85% at 24 and 48 h, respectively, by AxCAIL-13. Further, IL-13 significantly decreased PGE2 and macrophage inflammatory protein-1alpha production. These results demonstrate that increased expression of IL-13 via gene therapy may decrease RA-associated inflammation by reducing secretion of proinflammatory cytokines and PGE2.
- Published
- 2000
- Full Text
- View/download PDF
22. Soluble vascular cell adhesion molecule 1 mediation of monocyte chemotaxis in rheumatoid arthritis.
- Author
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Tokuhira M, Hosaka S, Volin MV, Haines GK 3rd, Katschke KJ Jr, Kim S, and Koch AE
- Subjects
- Arthritis, Rheumatoid metabolism, Arthritis, Rheumatoid physiopathology, Humans, Integrin alpha4beta1, Integrins biosynthesis, Integrins physiology, Macrophages metabolism, Monocytes metabolism, Receptors, Lymphocyte Homing biosynthesis, Receptors, Lymphocyte Homing physiology, Signal Transduction physiology, Solubility, Synovial Fluid cytology, Up-Regulation, Vascular Cell Adhesion Molecule-1 physiology, Arthritis, Rheumatoid pathology, Chemotaxis, Leukocyte drug effects, Monocytes cytology, Vascular Cell Adhesion Molecule-1 pharmacology
- Abstract
Objective: Rheumatoid arthritis (RA) is characterized by infiltration of leukocytes, including monocyte/ macrophages, into synovial tissue (ST), but factors mediating the ingress of these cells are poorly understood. Vascular cell adhesion molecule 1 (VCAM-1) plays an important role in adhesion of leukocytes to the vasculature. This study was undertaken to test the hypothesis that soluble VCAM-1 (sVCAM-1) might mediate chemotaxis of monocytes in RA., Methods: Chemotaxis assays were performed using a modified Boyden chamber to determine the effects of sVCAM-1 on and the role of very late activation antigen 4 (VLA-4) in peripheral blood (PB) monocyte migration. Synovial fluids (SF) were immunodepleted of sVCAM-1 to identify a role for sVCAM-1 in RA. Immunohistochemistry and flow cytometry analyses were performed to show the expression of VLA-4 in ST, SF, and PB. Tyrosine phosphorylation was studied by Western blot analysis on PB monocyte lysates in the presence of signaling inhibitors., Results: Soluble VCAM-1 induced monocyte migration in the nM range, in a concentration-dependent manner. Anti-VLA-4 significantly inhibited sVCAM-1-induced monocyte migration, suggesting that sVCAM-1 acts in part via a VLA-4-dependent mechanism. In RA SF, incubation with anti-VCAM-1 resulted in a reduction in the ability to induce monocyte migration (mean 28%). VLA-4 immunolocalized to RA ST, SF, or PB, monocytes, macrophages, and lymphocytes. Soluble VCAM-1 stimulated tyrosine phosphorylation in monocytes, and pertussis toxin, chelerythrine chloride, and staurosporine significantly reduced sVCAM-1-mediated monocyte chemotaxis, suggesting that signaling pathways via G proteins and protein kinase C are required for sVCAM-1-mediated monocyte migration., Conclusion: These results demonstrate a novel function for sVCAM-1 as a monocyte chemotactic agent in RA and suggest a new potential target for modulating monocyte ingress into inflamed RA ST.
- Published
- 2000
- Full Text
- View/download PDF
23. Interleukin-4 adenoviral gene therapy reduces production of inflammatory cytokines and prostaglandin E2 by rheumatoid arthritis synovium ex vivo.
- Author
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Woods JM, Tokuhira M, Berry JC, Katschke KJ Jr, Kurata H, Damergis JA Jr, Arai K, and Koch AE
- Subjects
- Adult, Aged, Arthritis, Rheumatoid virology, Cells, Cultured, Culture Media, Conditioned, Cytokines metabolism, Female, Fibroblasts metabolism, Fibroblasts virology, Genetic Vectors, Humans, Male, Middle Aged, Synovial Membrane virology, beta-Galactosidase metabolism, Adenoviridae genetics, Arthritis, Rheumatoid metabolism, Dinoprostone metabolism, Genetic Therapy, Interleukin-4 genetics, Synovial Membrane metabolism
- Abstract
Background: The rheumatoid arthritis (RA) joint is characterized by an inflammatory synovial pannus which mediates tissue destruction. Interleukin (IL)-4 reduces the production of many proinflammatory cytokines, particularly by activated macrophages. Therefore, we examined the ability of adenovirally delivered IL-4 for the treatment of human RA to reduce the secretion of proinflammatory molecules., Methods: Adenoviral vectors encoding the genes for human IL-4 (AxCAIL-4) and bacterial beta-galactosidase (AxCAlacZ) were generated and examined for appropriate production and biological activity. RA synovial tissue (ST) explants or fibroblasts were infected with AxCAIL-4 or a beta-galactosidase producing vector, as a control, and conditioned medium (CM) was collected for ELISA analysis., Results: AxCAIL-4 decreased the production of the inflammatory cytokines IL-1 beta and tumor necrosis factor-alpha in RA ST explant CM. IL-8 levels were significantly reduced by 71%, 88%, and 82% at 24, 48, and 72 hours, respectively, in RA ST explant CM. In the same CM, monocyte chemotactic protein-1 (MCP-1) levels decreased 60% at 48 hours. In contrast, RA synovial fibroblast CM levels of MCP-1 were increased by AxCAIL-4. Epithelial neutrophil activating peptide-78 levels produced by RA ST explants were significantly decreased by AxCAIL-4 by 88%, 92%, and 93% at 24, 48, and 72 hours, respectively. Growth related gene product-alpha levels were likewise decreased in RA ST explant CM. In ST explants as well as RA synovial fibroblasts, IL-4 treatment decreased prostaglandin E2 (PGE2) production., Conclusions: Increased expression of IL-4 via gene therapy may decrease RA-associated inflammation by reducing proinflammatory cytokines and PGE2.
- Published
- 1999
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