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Mouliou DS. C-Reactive Protein: Pathophysiology, Diagnosis, False Test Results and a Novel Diagnostic Algorithm for Clinicians. Diseases 2023; 11:132. [PMID: 37873776 PMCID: PMC10594506 DOI: 10.3390/diseases11040132] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 09/15/2023] [Accepted: 09/19/2023] [Indexed: 10/25/2023] Open
Abstract
The current literature provides a body of evidence on C-Reactive Protein (CRP) and its potential role in inflammation. However, most pieces of evidence are sparse and controversial. This critical state-of-the-art monography provides all the crucial data on the potential biochemical properties of the protein, along with further evidence on its potential pathobiology, both for its pentameric and monomeric forms, including information for its ligands as well as the possible function of autoantibodies against the protein. Furthermore, the current evidence on its potential utility as a biomarker of various diseases is presented, of all cardiovascular, respiratory, hepatobiliary, gastrointestinal, pancreatic, renal, gynecological, andrological, dental, oral, otorhinolaryngological, ophthalmological, dermatological, musculoskeletal, neurological, mental, splenic, thyroid conditions, as well as infections, autoimmune-supposed conditions and neoplasms, including other possible factors that have been linked with elevated concentrations of that protein. Moreover, data on molecular diagnostics on CRP are discussed, and possible etiologies of false test results are highlighted. Additionally, this review evaluates all current pieces of evidence on CRP and systemic inflammation, and highlights future goals. Finally, a novel diagnostic algorithm to carefully assess the CRP level for a precise diagnosis of a medical condition is illustrated.
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Yang C, Hou X, Feng Q, Li Y, Wang X, Qin L, Yang P. Lupus serum IgG induces microglia activation through Fc fragment dependent way and modulated by B-cell activating factor. J Transl Med 2019; 17:426. [PMID: 31864410 PMCID: PMC6925475 DOI: 10.1186/s12967-019-02175-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Accepted: 12/10/2019] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND Neuropsychiatric manifestations are frequent in patients with systemic lupus erythematosus (SLE), yet the etiology and pathogenesis of brain damage in SLE remains unclear. Because the production of autoantibodies, formation and deposition of immunocomplexes are major serological characteristics of SLE, the elevated level of serum immunoglobulin may contribute to brain tissue injury of SLE. To testify this, in this study, we examined whether immunoglobulin G (IgG) in the serum of SLE patients affects the cellular functions in central nervous system and the potential mechanism. METHODS In vivo intracerebral injection of SLE-serum in mouse was used to activate microglia and the production of pro-inflammatory cytokine was assessed by ELISA. Sera was divided into IgG and IgG depleted fractions, while IgG was further divided into Fc and Fab fragments to examine which part has an effect on microglia. Flow cytometry, immunofluorescence and quantitative PCR (qPCR) were used to verify the synergistic effect of B-cell activating factor (BAFF) on IgG stimulation of microglia. RESULTS We found that IgG in lupus sera can induce M1 activation of brain microglia following intraventricular injection into normal mice, and BAFF facilitates this process. In vitro, we identified that IgG bound to microglia through Fc rather than Fab fragments, and BAFF up-regulated the expression of Fc receptors (FcγR) on the surface of microglia, consequently, promote IgG binding to microglia. CONCLUSION Our results suggest that lupus serum IgG causes inflammatory responses of microglia by involving the Fc signaling pathway and the activity could be up-regulated by BAFF. Accordingly, disruption of the FcγR-mediated signaling pathway and blockade of microglia activation may be a therapeutic target in patients with neuropsychiatric lupus erythematosus.
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Affiliation(s)
- Chunshu Yang
- Department of 1st Cancer Institute, First Affiliated Hospital, China Medical University, Shenyang, 110001 People’s Republic of China
| | - Xiaoyu Hou
- Department of Rheumatology and Immunology, First Affiliated Hospital, China Medical University, Shenyang, 110001 People’s Republic of China
| | - Qianhui Feng
- Department of Rheumatology and Immunology, First Affiliated Hospital, China Medical University, Shenyang, 110001 People’s Republic of China
| | - Yingzhuo Li
- Department of Physiology, School of Life Science, China Medical University, Shenyang, 110122 People’s Republic of China
| | - Xuejiao Wang
- Department of Physiology, School of Life Science, China Medical University, Shenyang, 110122 People’s Republic of China
| | - Ling Qin
- Department of Physiology, School of Life Science, China Medical University, Shenyang, 110122 People’s Republic of China
| | - Pingting Yang
- Department of Rheumatology and Immunology, First Affiliated Hospital, China Medical University, Shenyang, 110001 People’s Republic of China
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Murinello S, Mullins RF, Lotery AJ, Perry VH, Teeling JL. Fcγ receptor upregulation is associated with immune complex inflammation in the mouse retina and early age-related macular degeneration. Invest Ophthalmol Vis Sci 2014; 55:247-58. [PMID: 24334446 DOI: 10.1167/iovs.13-11821] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Several lines of evidence suggest the involvement of antibodies and immune complex inflammation in AMD, a blinding disease with a strong inflammatory component. To examine this further, we developed a novel experimental mouse model of retinal inflammation and evaluated whether inflammation associated with immune complex formation was present in eyes of AMD donors. METHODS A localized immune complex-mediated reaction was induced in the retina of wild-type (WT), Fc receptor γ chain-deficient (γ(-/-)), and C1q-deficient (C1q(-/-)) mice, and donor eyes were obtained after death from donors with early or wet AMD and from healthy control subjects. The presence of immune complexes, Fcγ receptors (FcγRs), and markers of macrophage/microglia activation was investigated by immunohistochemistry. RESULTS In WT and C1q(-/-) mice, immune complex deposition in the retina led to a robust inflammatory response with activation of microglia, recruitment of myeloid cells, and increased expression of FcγRI through FcγRIV and major histocompatibility complex class II. This response was not observed in γ(-/-) mice lacking activating FcγRs. We found that early AMD was associated with deposition of IgG, C1q, and membrane attack complex in the choriocapillaris and with increased numbers of CD45+ cells expressing FcγRIIa and FcγRIIb. Furthermore, FcγRIIa and FcγRIIb were observed in eyes of donors with wet AMD. CONCLUSIONS Our studies suggest that immune complexes may contribute to AMD pathogenesis through interaction of IgG with FcγRs and might inform about possible adverse effects associated with therapeutic antibodies.
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Affiliation(s)
- Salome Murinello
- Centre for Biological Sciences, University of Southampton, Southampton General Hospital, Southampton, United Kingdom
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Teeling JL, Carare RO, Glennie MJ, Perry VH. Intracerebral immune complex formation induces inflammation in the brain that depends on Fc receptor interaction. Acta Neuropathol 2012; 124:479-90. [PMID: 22618994 PMCID: PMC3444701 DOI: 10.1007/s00401-012-0995-3] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Accepted: 05/06/2012] [Indexed: 12/28/2022]
Abstract
In this study, we investigate the underlying mechanisms of antibody-mediated inflammation in the brain. We show that immune complexes formed in the brain parenchyma generate a robust and long-lasting inflammatory response, characterized by increased expression of the microglia markers CD11b, CD68 and FcRII/III, but no neutrophil recruitment. In addition to these histological changes, we observed transient behavioural changes that coincided with the inflammatory response in the brain. The inflammatory and behavioural changes were absent in Fc-gamma chain (Fcγ)-deficient mice, while C1q-deficient mice were not different from wild-type mice. We conclude that, in the presence of antigen, antibodies can lead to a local immune complex-mediated inflammatory reaction in the brain parenchyma and indirectly induce neuronal tissue damage through recruitment and activation of microglia via Fcγ receptors. These observations may have important implications for the development of therapeutic antibodies directed against neuronal antigens used for therapeutic intervention in neurological diseases.
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Affiliation(s)
- Jessica L Teeling
- Centre for of Biological Sciences, University of Southampton, Southampton General Hospital, UK.
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Biocompatible microspheres based on acetylated polysaccharide prepared from water-in-oil-in-water (W1/O/W2) double-emulsion method for delivery of type II diabetic drug (exenatide). Colloids Surf A Physicochem Eng Asp 2009. [DOI: 10.1016/j.colsurfa.2009.03.015] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Extravasations and emigration of neutrophils to the inflammatory site depend on the interaction of immune-complex with Fcgamma receptors and can be effectively blocked by decoy Fcgamma receptors. Blood 2007; 111:894-904. [PMID: 17962513 DOI: 10.1182/blood-2007-04-085944] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Extravasation and emigration of neutrophils to the site of inflammation are essential early steps in the initiation of many antibody-mediated autoimmune diseases. The Fc domains of cell bound autoantibodies or immune-complexes (IC) are capable of triggering the neutrophil emigration via complement and FcgammaRs-mediated mechanisms. To define the clinical relevance and the relative contribution of these 2 pathways in IC-mediated neutrophil emigration, we have neutralized the FcgammaR-binding activity of IC with a recombinant dimeric Fc receptor, CD16A-Ig, and investigated the early events of IC-induced inflammation in mice. Systemic administration of purified CD16A-Ig blocked IC-induced inflammation, mast- cell degranulation, and extravasation of neutrophils in a reversed Arthus reaction. Although the binding of CD16A-Ig to IC did not alter the complement-activating properties of IC, no evidence for complement-dependent neutrophil emigration was observed. These results suggest that interaction of IC with cells expressing FcgammaRs at the inflammatory site results in the secretion of chemoattractants, which mediate complement-independent emigration of neutrophils in this cutaneous acute inflammation model. Furthermore, blocking the interaction of IC to FcgammaRs expressed on inflammatory cells by administering high-avidity Fc fusion dimers of low-affinity FcgammaRs is an effective way of preventing IC-induced acute inflammation in autoimmune diseases.
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Lee ES, Park KH, Kang D, Park IS, Min HY, Lee DH, Kim S, Kim JH, Na K. Protein complexed with chondroitin sulfate in poly(lactide-co-glycolide) microspheres. Biomaterials 2007; 28:2754-62. [PMID: 17337049 DOI: 10.1016/j.biomaterials.2007.01.049] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2006] [Accepted: 01/23/2007] [Indexed: 12/15/2022]
Abstract
Chondroitin sulfate (CsA) is an acidic mucopolysaccharide, which is able to form ionic complexes with positively charged proteins. In this study, a protein-CsA complex was constructed to nano-sized particles. Zeta potential measurements revealed that a CsA-to-protein fraction of greater than 0.1 results in a neutralization of the positive charge on lysozyme (Lys). Based on this preliminary study, we have prepared poly(lactide-co-glycolide) (PLGA) microspheres harboring Lys/CsA complexes via the multi-emulsion method. Protein stability in the PLGA microspheres was preserved during both microsphere preparation and protein release. The profiles of Lys release from the PLGA microspheres evidenced nearly zero-order kinetics, depending on the quantity of CsA. An in vivo fluorescent image of experimental mouse tissue showed that the PLGA microspheres with the Lys/CsA complex had released the entirety of their Lys without no residual amount after 23 days, but microspheres without the complex harbored a great deal of residual Lys, which is attributable to its degradation by acidic PLGA degradates. The tissue reaction evidenced by the PLGA microspheres stabilized with CsA showed minimal foreign body reaction and little configuration of immune cells including neutrophils and macrophages, but the reactions of the PLGA microspheres without CsA were characterized by a relatively elevated inflammation. These results show that CsA is a viable candidate for long-acting micro-particular protein delivery.
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Affiliation(s)
- Eun Seong Lee
- Department of Pharmaceutics and Pharmaceutical Chemistry, University of Utah, Salt Lake City, UT 84108, USA
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Sindrilaru A, Seeliger S, Ehrchen JM, Peters T, Roth J, Scharffetter-Kochanek K, Sunderkötter CH. Site of blood vessel damage and relevance of CD18 in a murine model of immune complex-mediated vasculitis. J Invest Dermatol 2006; 127:447-54. [PMID: 17008881 DOI: 10.1038/sj.jid.5700563] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
How neutrophils (polymorphonuclear neutrophils, PMNs) damage vessels in leukocytoclastic vasculitis (LcV) mediated by immune complexes (ICs) is unclear. If degradative enzymes and oxygen radicals are released from PMNs while adhering to the inner side of the vessel wall, they could be washed away by the blood stream or neutralized by serum protease inhibitors. We investigated if in LcV PMNs could damage vessels from the tissue side after transmigration. We used CD18-deficient (CD18-/-) mice because the absence of CD18 excludes transmigration of PMNs. When eliciting the Arthus reaction in ears of CD18-/- mice, deposition of ICs was not sufficient to recruit PMNs or to induce IC-mediated LcV. Injection of PMNs intradermally in CD18-/- mice allowed us to investigate if bypassing diapedesis and placing PMNs exclusively on the abluminal side leads to vascular destruction. We found that injected PMNs gathered around perivascular ICs, but did not cause vessel damage. Only intravenous injection of wild-type PMNs could re-establish the Arthus reaction in CD18-/- mice. Thus, PMNs cause vessel damage during diapedesis from the luminal side, but not from the perivascular space. We suggest that in order to shield the cytotoxic products from the blood stream, ICs induce particularly tight interactions between them, PMNs and endothelial cells.
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Affiliation(s)
- Anca Sindrilaru
- Institute of Experimental Dermatology, University Hospital Münster, Münster, Germany
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Stokol T, O'Donnell P, Xiao L, Knight S, Stavrakis G, Botto M, von Andrian UH, Mayadas TN. C1q governs deposition of circulating immune complexes and leukocyte Fcgamma receptors mediate subsequent neutrophil recruitment. ACTA ACUST UNITED AC 2004; 200:835-46. [PMID: 15466618 PMCID: PMC2213287 DOI: 10.1084/jem.20040501] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Inflammation induced by circulating immunoglobulin G–immune complexes (ICs) characterizes many immune-mediated diseases. In this work, the molecular requirements for the deposition of circulating ICs and subsequent acute leukocyte recruitment in mice were elucidated. We show that after intravenous injection, preformed soluble ICs are rapidly deposited in the postcapillary venules of the cremaster microcirculation, secondary to increased vascular permeability. This deposition is dependent on complement C1q. IC deposition is associated with leukocyte recruitment. Leukocyte rolling, which is mediated by P-selectin in the exteriorized cremaster muscle, is not further increased in response to ICs. In contrast, leukocyte rolling velocity is significantly decreased and leukocyte adhesion is significantly increased in the presence of ICs. The IC-mediated slow leukocyte rolling velocity and subsequent adhesion and emigration are dependent on Fcγ receptors (FcγRs), particularly FcγRIII, with complement C3 and C5 having no detectable role. These studies suggest a regulatory mechanism of IC deposition and leukocyte trafficking in IC-mediated inflammation requiring C1q and FcγRs in sequential, noninteracting roles.
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Affiliation(s)
- Tracy Stokol
- Department of Pathology, Brigham and Women's Hospital, Boston, MA 02115, USA
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Korompilias AV, Gilkeson GS, Seaber AV, Urbaniak JR. Hemorrhage and thrombus formation in early experimental osteonecrosis. Clin Orthop Relat Res 2001:11-8. [PMID: 11347823 DOI: 10.1097/00003086-200105000-00003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The aim of the current study was to test the hypothesis that the induction of an underlying immunologic condition in rabbits may enhance the development of steroid-induced osteonecrosis. Thirty-five adult rabbits were divided into four groups. Group I: 10 rabbits were immunized at 15-day intervals for 2 months by murine antibodies to deoxyribonucleic acid autoantibodies. Four weeks after the end of the immunization, the animals received injections of methylprednisolone for 7 days and then prednisolone per os for 8 months. Group II: 10 animals only received immunizations according to the protocol used in Group I. Group III: 10 animals only were treated with corticosteroids according to the protocol used in Group I. Group IV: five animals were used as controls. Various changes were observed in the proximal metaphysis and diaphysis of the femur in eight of 10 animals in Group I (80%) and in five of 10 animals in Group II (50%) when compared with the animals in Group III and Group IV. The most common feature was evidence of new and old hemorrhage through the sinusoids, exudative reaction and thrombus formation in veins and small arteries. Focal necrotic areas of bone marrow showed an accumulation of cell debris, residue of hemorrhage, and disappearance of marrow elements. These findings suggest that (1) corticosteroids may potentiate the effects of a preexisting condition to increase the risk of osteonecrosis; (2) immunologic reaction may be an important factor in the pathogenesis of necrotic lesions; and (3) repeated intramedullary hemorrhage and thrombus formation may represent early major pathologic findings in bone necrosis.
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Affiliation(s)
- A V Korompilias
- Department of Orthopaedic Surgery, University of Ioannina, Greece
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11
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Nakata K, Masuhara K, Nakamura N, Shibuya T, Sugano N, Matsui M, Ochi T, Ohzono K. Inducible osteonecrosis in a rabbit serum sickness model: deposition of immune complexes in bone marrow. Bone 1996; 18:609-15. [PMID: 8806003 DOI: 10.1016/8756-3282(96)00078-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We established inducible osteonecrosis in a rabbit serum sickness model. Osteonecrosis with marrow necrosis could be induced by the intravenous injection of horse serum in two doses separated in time by a period of three weeks. In this model, osteonecrosis could be successfully produced in rabbit femoral metaphysis. The incidence of marrow necrosis was 45% (9 of 20 rabbits) and trabecular necrosis occurred in 6 of 20 rabbits (30%) at 7 days after the second injection of the horse serum. In bone marrow of the femoral metaphysis, extravasation of erythrocytes and the formation of micro-thrombi in arterioles were often observed in an early stage of the present model and both findings correlate well each other (p = 0.0001). Immune complexes could be demonstrated using immunohistochemistry in bone marrow of the femoral metaphysis as well as in glomeruli of the kidney. Extravasation of erythrocytes in bone marrow of the femoral metaphysis was observed in 8 of 12 (67%) cases with immune complex deposition in the sinusoidal space of the femoral metaphysis and in 12 of 21 (57%) cases with immune complex deposition in glomeruli of the kidney. Immune complex deposition both in the sinusoidal space of femoral bone marrow (p = 0.0385) and in glomeruli of the kidney (p = 0.0209) closely related to extravasation of erythrocytes and microthrombi in arterioles in the early stage of this model. Early microcirculatory injury (extravasation of erythrocytes and microthrombi in arterioles) adjacent to osteonecrosis could be induced by immune complex deposition in femoral bone marrow and might be predictable characteristics for the inducible osteonecrosis in the present serum sickness model. The important findings in this study were that early microcirculatory injury was closely related to the deposition of immune complexes in femoral bone marrow, and that early microcirculatory injury associated with immune complex deposition was located close to osteonecrotic regions.
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Affiliation(s)
- K Nakata
- Department of Orthopaedic Surgery, Osaka University Medical School, Japan
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12
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Haas DA, Nakanishi O, MacMillan RE, Jordan RC, Hu JW. Development of an orofacial model of acute inflammation in the rat. Arch Oral Biol 1992; 37:417-22. [PMID: 1610310 DOI: 10.1016/0003-9969(92)90026-5] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
An appropriate model was created by the paraperiosteal injection of mustard oil (20% allyl isothiocyanate dissolved in mineral oil) into the periarticular temporomandibular tissue of anaesthetized rats. Inflammation was assessed by the plasma extravasation of Evans' blue dye bound to plasma protein. This was confirmed visually and compared spectrophotometrically with the contralateral untreated control site (p less than 0.0005). A time-course study of the effect of mustard oil on Evans' blue extravasation revealed a gradually increasing effect that was maximal at 30 min after administration, with no further increase at 60 min. A dose-response study showed that giving 30 microliters of 20% mustard oil produced the maximal effect, with no further increase from 50 microliters. To confirm induction of inflammation, polymorphonuclear neutrophil infiltration was assessed morphometrically and found to increase in the treated tissue compared with the contralateral untreated control (p less than 0.001).
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Affiliation(s)
- D A Haas
- Faculty of Dentistry, University of Toronto, Ontario, Canada
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Morris DD. Endotoxemia in horses. A review of cellular and humoral mediators involved in its pathogenesis. Vet Med (Auckl) 1991; 5:167-81. [PMID: 1920254 DOI: 10.1111/j.1939-1676.1991.tb00944.x] [Citation(s) in RCA: 97] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Endotoxemia remains the leading cause of death in horses, being intimately involved in the pathogenesis of gastrointestinal disorders that cause colic and neonatal foal septicemia. Endotoxins, normally present within the bowel, gain access to the blood across damaged intestinal mucosa, or endotoxemia occurs when gram negative organisms proliferate in tissues. Endotoxins are removed from the circulation by the mononuclear phagocyte system, and the response of mononuclear phagocytes to these lipopolysaccharides (LPS) play an important role in determining the severity of clinical disease. Macrophages become highly activated for enhanced secretory, phagocytic and cidal functions by LPS. Macrophage-derived cytokines are responsible for many of the pathophysiologic consequences of endotoxemia. The arachidonic acid metabolites, prostacyclin and thromboxane A2 likely mediate early hemodynamic dysfunction and the leukotrienes may potentiate tissue ischemia during endotoxemia. Interleukin 1 (IL-1) induces fever and is responsible for the inflammatory cascade, which constitutes the acute phase response. Tumor necrosis factor (TNF), an important proximal mediator of the effects of LPS, acts to initiate events and formation of other molecules that affect shock and tissue injury. Systemic administration of TNF produces most of the physiologic derangements that are associated with endotoxemia and antibodies that are directed against TNF significantly reduce LPS-induced mortality in experimental animals. In response to endotoxins, mononuclear phagocytes express thromboplastin-like procoagulant activity (PCA), which initiates microvascular thrombosis. Both IL-1 and TNF induce PCA expression, creating a positive feedback loop for LPS-induced coagulopathy. A macrophage-derived platelet activating factor contributes to coagulation dysfunction and further stimulates arachidonic acid metabolism. The ultimate consequences of endotoxemia are multiple system organ failure and death. The numerous feedback loops and intertwining cascades of mediators during endotoxemia defy simplistic methods of treatment. The optimal therapy likely involves methods to alter the generation of inflammatory mediators by mononuclear phagocytes.
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Affiliation(s)
- D D Morris
- Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens 30602
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Issekutz AC, Roland DM, Patrick RA. The effect of FUT-175 (Nafamstat Mesilate) on C3a, C4a and C5a generation in vitro and inflammatory reactions in vivo. INTERNATIONAL JOURNAL OF IMMUNOPHARMACOLOGY 1990; 12:1-9. [PMID: 2303313 DOI: 10.1016/0192-0561(90)90062-r] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
FUT-175 is a synthetic protease inhibitor and an inhibitor of the classical and alternate pathways of complement activation. In human serum, FUT-175 inhibited C3a, C4a and C5a generation induced by heat aggregated IgG, zymosan and Cobra venom factor with IC50 values in the range of 3-43 microM depending on the stimulus and the fragments. To assess in vivo anti-inflammatory activity, inflammatory reactions induced in the skin of rabbits were quantitated by using 125I-albumin extravasation, 51Cr-labelled leukocyte accumulation and 86RbCl accumulation as a measure of hyperemia. Infusion of FUT-175 at 2 mg/kg/h inhibited all three parameters by 50-80% in dermal reactions induced by killed E. coli, zymosan, immune complexes, the reversed Arthus reaction, zymosan activated plasma (ZAP), f-norleu-leu-phe (FNLP) and LTB4. In contrast, the response to endotoxin (0.1 microgram) was not effected by FUT-175 treatment. The effect of FUT-175 was comparable to that of local or systemic therapy with indomethacin, but unlike indomethacin, the effect of FUT-175 was not reversed by local PGE2 administration. Furthermore, indomethacin and FUT-175 had additive anti-inflammatory effects. These results suggest that although FUT-175 is a potent inhibitor of C3a, C4a and C5a generation, it has novel and broad anti-inflammatory effects, possibly through actions in addition to complement inhibition as indicated by inhibition of FNLP-, LTB4- and ZAP-induced reactions.
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Affiliation(s)
- A C Issekutz
- Department of Pediatrics and Microbiology, Dalhousie University, Halifax, Nova Scotia, Canada
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15
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Huber AR, Weiss SJ. Disruption of the subendothelial basement membrane during neutrophil diapedesis in an in vitro construct of a blood vessel wall. J Clin Invest 1989; 83:1122-36. [PMID: 2703527 PMCID: PMC303798 DOI: 10.1172/jci113992] [Citation(s) in RCA: 158] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
To examine the course of physiologic interactions between extravasating neutrophils and the subendothelial basement membrane, a model of the venular vessel wall was constructed by culturing human umbilical vein endothelial cells on a collagen matrix. After 21 d in culture, the endothelial cell monolayer displayed in vivo-like intercellular borders and junctions, deposited a single-layered, continuous basement membrane that was impenetrable to colloidal particles, and supported neutrophil extravasation in a physiologic manner. Using this model, we demonstrate that neutrophil transmigration in a plasma milieu was associated with a significant disruption of the retentive properties of the basement membrane in the absence of discernable morphologic changes. The loss of basement membrane integrity associated with neutrophil diapedesis was not dependent on neutrophil elastase or cathepsin G and was resistant to inhibitors directed against neutrophil collagenase, gelatinase, and heparanase. Despite the fact that this loss in matrix integrity could not be prevented, basement membrane defects were only transiently expressed before they were repaired by the overlying endothelium via a mechanism that required active protein and RNA synthesis. These data indicate that neutrophil extravasation and reversible basement membrane disruption are coordinated events that occur as a consequence of vessel wall transmigration.
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Affiliation(s)
- A R Huber
- Department of Internal Medicine, University of Michigan, Ann Arbor 48109
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Williams TJ, Hellewell PG, Jose PJ. Inflammatory mechanisms in the Arthus reaction. AGENTS AND ACTIONS 1986; 19:66-72. [PMID: 2879431 DOI: 10.1007/bf01977260] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Fletcher DS, Osinga D, Bonney RJ. Role of polymorphonuclear leukocytes in connective tissue breakdown during the reverse passive Arthus reaction. Biochem Pharmacol 1986; 35:2601-6. [PMID: 3017358 DOI: 10.1016/0006-2952(86)90059-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The reverse passive Arthus (RPA) reaction performed in the skin of rats was modified to allow for the determination of polymorphonuclear leukocyte (PMN) infiltration and hemorrhage, as well as changes in vascular permeability. After initiation of the RPA reaction, PMN infiltration, monitored by measurement of tissue myeloperoxidase (MPO, EC 1.11.1.7) content, increased dramatically with time. Depending on the experimental conditions used, PMN accumulation reached a maximum 2-10 hr after increased vascular permeability (125I-labeled albumin content) had peaked. Hemorrhage (59Fe-labeled erythrocyte accumulation) began to occur only after significant levels of PMN were reached and continued to increase proportionately to the level of PMN infiltration attained. Indomethacin administered 30 min prior to initiating the RPA reaction had no effect on vascular permeability increase but suppressed both PMN accumulation and hemorrhage development about 50%. When indomethacin was given 2 hr after the RPA reaction was begun, no effect on any of the RPA variables was noted. Dexamethasone suppressed the increase in vascular permeability (53%), PMN accumulation (78%), and hemorrhage (90%) when given 30 min prior to initiation of the reaction. Dexamethasone given 2 hr after initiating the RPA suppressed the entire reaction, but to a lesser extent. Catalase, as well as trasylol, alpha-1-antiproteinase and soybean trypsin inhibitor, inhibited PMN accumulation as well as hemorrhage when given intravenously at plus 2 hr. These results indicate that the damage to blood vessels during a severe RPA reaction is a direct consequence of PMN activity.
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