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Abstract
The complement cascade comprises soluble and cell surface proteins and is an important arm of the innate immune system. Once activated, the complement system rapidly generates large quantities of protein fragments that are potent mediators of inflammatory, vasoactive and metabolic responses. Although complement is crucial to host defence and homeostasis, its inappropriate or uncontrolled activation can also drive tissue injury. For example, the complement system has been known for more than 50 years to be activated by glomerular immune complexes and to contribute to autoimmune kidney disease. Notably, the latest research shows that complement is also activated in kidney diseases that are not traditionally thought of as immune-mediated, including haemolytic-uraemic syndrome, diabetic kidney disease and focal segmental glomerulosclerosis. Several complement-targeted drugs have been approved for the treatment of kidney disease, and additional anti-complement agents are being investigated in clinical trials. These drugs are categorically different from other immunosuppressive agents and target pathological processes that are not effectively inhibited by other classes of immunosuppressants. The development of these new drugs might therefore have considerable benefits in the treatment of kidney disease.
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Affiliation(s)
- Vojtech Petr
- Institute for Clinical and Experimental Medicine, Prague, Czech Republic
- University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Joshua M Thurman
- University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.
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2
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Abstract
Increasing evidence indicates an integral role for the complement system in the deleterious inflammatory reactions that occur during critical phases of the transplantation process, such as brain or cardiac death of the donor, surgical trauma, organ preservation and ischaemia-reperfusion injury, as well as in humoral and cellular immune responses to the allograft. Ischaemia is the most common cause of complement activation in kidney transplantation and in combination with reperfusion is a major cause of inflammation and graft damage. Complement also has a prominent role in antibody-mediated rejection (ABMR) owing to ABO and HLA incompatibility, which leads to devastating damage to the transplanted kidney. Emerging drugs and treatment modalities that inhibit complement activation at various stages in the complement cascade are being developed to ameliorate the damage caused by complement activation in transplantation. These promising new therapies have various potential applications at different stages in the process of transplantation, including inhibiting the destructive effects of ischaemia and/or reperfusion injury, treating ABMR, inducing accommodation and modulating the adaptive immune response.
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3
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Cheng L, Gou S, Qiu H, Ma L, Fu P. Complement regulatory proteins in kidneys of patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis. Clin Exp Immunol 2018; 191:116-124. [PMID: 28940198 PMCID: PMC5721235 DOI: 10.1111/cei.13051] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/19/2017] [Indexed: 02/05/2023] Open
Abstract
The complement system activation is involved in the development of anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV). The study aimed to investigate the expression of complement regulatory proteins (CRPs) CD46, CD55 and CD59 in kidneys of 51 AVV patients. The expression of CD46, CD55 and CD59 in kidneys was detected by immunohistochemistry and double immunofluorescence staining. The immunohistochemical examination revealed that expression of the three CRPs could be detected in the glomeruli and tubules of both AAV patients and normal controls. The expression levels of the three CRPs in glomeruli of patients with AAV were significantly lower than those of normal controls. The scores of CD46 and CD55 expression in the tubules of AAV patients were significantly lower than those of normal controls, while there was no significant difference between the scores of CD59 expression in tubules of AAV patients and those of normal controls. Among AAV patients, the expression level of CD46 in glomeruli correlated inversely with the proportion of normal glomeruli, while it correlated with tubular atrophy in renal interstitium (r = -0·305, P = 0·026; r = 0·330, P = 0·023, respectively). The expression levels of CD55 and CD59 in glomeruli correlated with the proportion of total crescents (r = 0·384, P = 0·006; r = 0·351, P = 0·011, respectively). Double immunofluorescence staining indicated that all three CRPs were expressed on endothelial cells, podocytes and mesangial cells in glomeruli. The expression levels of the three CRPs were dysregulated in kidneys of patients with AAV. The expression levels of CD46, CD55 and CD59 were associated with the severity of renal injury of AAV patients.
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Affiliation(s)
- L. Cheng
- Division of NephrologyKidney Research Institute, West China Hospital of Sichuan UniversityChengduChina
| | - S.‐J. Gou
- Division of NephrologyKidney Research Institute, West China Hospital of Sichuan UniversityChengduChina
| | - H.‐Y. Qiu
- Division of NephrologyKidney Research Institute, West China Hospital of Sichuan UniversityChengduChina
| | - L. Ma
- Division of NephrologyKidney Research Institute, West China Hospital of Sichuan UniversityChengduChina
| | - P. Fu
- Division of NephrologyKidney Research Institute, West China Hospital of Sichuan UniversityChengduChina
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Mizuno M, Suzuki Y, Ito Y. Complement regulation and kidney diseases: recent knowledge of the double-edged roles of complement activation in nephrology. Clin Exp Nephrol 2017; 22:3-14. [DOI: 10.1007/s10157-017-1405-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Accepted: 03/14/2017] [Indexed: 12/28/2022]
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González-Molina M, Ruiz-Esteban P, Caballero A, Burgos D, Cabello M, Leon M, Fuentes L, Hernandez D. Immune response and histology of humoral rejection in kidney transplantation. Nefrologia 2016; 36:354-67. [PMID: 27267916 DOI: 10.1016/j.nefro.2016.03.023] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Revised: 02/22/2016] [Accepted: 03/26/2016] [Indexed: 11/15/2022] Open
Abstract
The adaptive immune response forms the basis of allograft rejection. Its weapons are direct cellular cytotoxicity, identified from the beginning of organ transplantation, and/or antibodies, limited to hyperacute rejection by preformed antibodies and not as an allogenic response. This resulted in allogenic response being thought for decades to have just a cellular origin. But the experimental studies by Gorer demonstrating tissue damage in allografts due to antibodies secreted by B lymphocytes activated against polymorphic molecules were disregarded. The special coexistence of binding and unbinding between antibodies and antigens of the endothelial cell membranes has been the cause of the delay in demonstrating the humoral allogenic response. The endothelium, the target tissue of antibodies, has a high turnover, and antigen-antibody binding is non-covalent. If endothelial cells are attacked by the humoral response, immunoglobulins are rapidly removed from their surface by shedding and/or internalization, as well as degrading the components of the complement system by the action of MCP, DAF and CD59. Thus, the presence of complement proteins in the membrane of endothelial cells is transient. In fact, the acute form of antibody-mediated rejection was not demonstrated until C4d complement fragment deposition was identified, which is the only component that binds covalently to endothelial cells. This review examines the relationship between humoral immune response and the types of acute and chronic histological lesion shown on biopsy of the transplanted organ.
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Affiliation(s)
- Miguel González-Molina
- Nephrology Department, Regional University Hospital of Malaga, Malaga University, IBIMA, REDINREN RD12/0021/0015, Malaga, Spain.
| | - Pedro Ruiz-Esteban
- Nephrology Department, Regional University Hospital of Malaga, Malaga University, IBIMA, REDINREN RD12/0021/0015, Malaga, Spain
| | - Abelardo Caballero
- Immunology Department, Regional University Hospital of Malaga, Malaga University, IBIMA, REDINREN RD12/0021/0015, Malaga, Spain
| | - Dolores Burgos
- Nephrology Department, Regional University Hospital of Malaga, Malaga University, IBIMA, REDINREN RD12/0021/0015, Malaga, Spain
| | - Mercedes Cabello
- Nephrology Department, Regional University Hospital of Malaga, Malaga University, IBIMA, REDINREN RD12/0021/0015, Malaga, Spain
| | - Miriam Leon
- Pathology Department, Regional University Hospital of Malaga, Malaga University, IBIMA, REDINREN RD12/0021/0015, Malaga, Spain
| | - Laura Fuentes
- Nephrology Department, Regional University Hospital of Malaga, Malaga University, IBIMA, REDINREN RD12/0021/0015, Malaga, Spain
| | - Domingo Hernandez
- Nephrology Department, Regional University Hospital of Malaga, Malaga University, IBIMA, REDINREN RD12/0021/0015, Malaga, Spain
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Yamanaka K, Kakuta Y, Miyagawa S, Nakazawa S, Kato T, Abe T, Imamura R, Okumi M, Maeda A, Okuyama H, Mizuno M, Nonomura N. Depression of Complement Regulatory Factors in Rat and Human Renal Grafts Is Associated with the Progress of Acute T-Cell Mediated Rejection. PLoS One 2016; 11:e0148881. [PMID: 26928779 PMCID: PMC4771804 DOI: 10.1371/journal.pone.0148881] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Accepted: 01/25/2016] [Indexed: 01/02/2023] Open
Abstract
Background The association of complement with the progression of acute T cell mediated rejection (ATCMR) is not well understood. We investigated the production of complement components and the expression of complement regulatory proteins (Cregs) in acute T-cell mediated rejection using rat and human renal allografts. Methods We prepared rat allograft and syngeneic graft models of renal transplantation. The expression of Complement components and Cregs was assessed in the rat grafts using quantitative real-time PCR (qRT-PCR) and immunofluorescent staining. We also administered anti-Crry and anti-CD59 antibodies to the rat allograft model. Further, we assessed the relationship between the expression of membrane cofactor protein (MCP) by immunohistochemical staining in human renal grafts and their clinical course. Results qRT-PCR results showed that the expression of Cregs, CD59 and rodent-specific complement regulator complement receptor 1-related gene/protein-y (Crry), was diminished in the rat allograft model especially on day 5 after transplantation in comparison with the syngeneic model. In contrast, the expression of complement components and receptors: C3, C3a receptor, C5a receptor, Factor B, C9, C1q, was increased, but not the expression of C4 and C5, indicating a possible activation of the alternative pathway. When anti-Crry and anti-CD59 mAbs were administered to the allograft, the survival period for each group was shortened. In the human ATCMR cases, the group with higher MCP expression in the grafts showed improved serum creatinine levels after the ATCMR treatment as well as a better 5-year graft survival rate. Conclusions We conclude that the expression of Cregs in allografts is connected with ATCMR. Our results suggest that controlling complement activation in renal grafts can be a new strategy for the treatment of ATCMR.
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Affiliation(s)
- Kazuaki Yamanaka
- Department of Urology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Yoichi Kakuta
- Department of Urology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
- * E-mail: (YK); (SM)
| | - Shuji Miyagawa
- Division of Organ Transplantation, Department of Surgery, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
- * E-mail: (YK); (SM)
| | - Shigeaki Nakazawa
- Department of Urology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Taigo Kato
- Department of Urology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Toyofumi Abe
- Department of Urology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Ryoichi Imamura
- Department of Urology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Masayoshi Okumi
- Department of Urology, Tokyo Women's Medical University, Shinjuku-ku, Tokyo, Japan
| | - Akira Maeda
- Division of Organ Transplantation, Department of Surgery, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Hiroomi Okuyama
- Division of Organ Transplantation, Department of Surgery, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Masashi Mizuno
- Department of Nephrology and Renal Replacement Therapy, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan
| | - Norio Nonomura
- Department of Urology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
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8
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Abstract
Activation of the complement system is tightly regulated by plasma and cell-associated complement regulatory proteins (CRPs), such as factor H (fH), decay-accelerating factor, and membrane cofactor protein. Animal models of disease have provided considerable insights into the important roles for CRPs in the kidney. Mice deficient in fH have excessive fluid phase C3 activation and inactivation, leading to deposition of inactivated C3b in glomerular capillary walls (GCW), comparable with dense deposit disease. In contrast, when fH lacks C-terminal surface targeting regions, local activation on the GCW leads to a disease reminiscent of thrombotic microangiopathy. The uniquely rodent protein, CR1-related y (Crry), has features analogous to human membrane cofactor protein. Defective Crry leads to unrestricted alternative pathway activation in the tubulointerstitium, resulting in pathologic features ranging from thrombotic microangiopathy (TMA), acute kidney injury, and tubulointerstitium nephritis. In the presence of initiators of the classic or lectin pathways, commonly in the form of immune complexes in human glomerular diseases, complement regulation is stressed, with the potential for recruitment of the spontaneously active alternative pathway. The threshold for this activation is set by CRPs; pathology is more likely when complement regulation is defective. Within the endocapillary region of the GCW, fH is key, while decay-accelerating factor and Crry are protective on mesangial cells and podocytes. Arguably, acquired alterations in these CRPs is a more common event, extending from pathologic states of cellular injury or production of inhibitory antibodies, to physiological fine tuning of the adaptive immune response.
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Membrane-bound complement regulatory proteins as biomarkers and potential therapeutic targets for SLE. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013; 735:55-81. [PMID: 23402019 DOI: 10.1007/978-1-4614-4118-2_4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
For the last two decades, there had been remarkable advancement in understanding the role of complement regulatory proteins in autoimmune disorders and importance of complement inhibitors as therapeutics. Systemic lupus erythematosus is a prototype of systemic autoimmune disorders. The disease, though rare, is potentially fatal and afflicts women at their reproductive age. It is a complex disease with multiorgan involvement, and each patient presents with a different set of symptoms. The diagnosis is often difficult and is based on the diagnostic criteria set by the American Rheumatology Association. Presence of antinuclear antibodies and more specifically antidouble-stranded DNA indicates SLE. Since the disease is multifactorial and its phenotypes are highly heterogeneous, there is a need to identify multiple noninvasive biomarkers for SLE. Lack of validated biomarkers for SLE disease activity or response to treatment is a barrier to the efficient management of the disease, drug discovery, as well as development of new therapeutics. Recent studies with gene knockout mice have suggested that membrane-bound complement regulatory proteins (CRPs) may critically determine the sensitivity of host tissues to complement injury in autoimmune and inflammatory disorders. Case-controlled and followup studies carried out in our laboratory suggest an intimate relation between the level of DAF, MCP, CR1, and CD59 transcripts and the disease activity in SLE. Based on comparative evaluation of our data on these four membrane-bound complement regulatory proteins, we envisaged CR1 and MCP transcripts as putative noninvasive disease activity markers and the respective proteins as therapeutic targets for SLE. Following is a brief appraisal on membrane-bound complement regulatory proteins DAF, MCP, CR1, and CD59 as biomarkers and therapeutic targets for SLE.
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Farrar CA, Asgari E, Schwaeble WJ, Sacks SH. Which pathways trigger the role of complement in ischaemia/reperfusion injury? Front Immunol 2012; 3:341. [PMID: 23181062 PMCID: PMC3500775 DOI: 10.3389/fimmu.2012.00341] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Accepted: 10/25/2012] [Indexed: 01/04/2023] Open
Abstract
Investigations into the role of complement in ischemia/reperfusion (I/R) injury have identified common effector mechanisms that depend on the production of C5a and C5b-9 through the cleavage of C3. These studies have also defined an important role for C3 synthesized within ischemic kidney. Less clear however is the mechanism of complement activation that leads to the cleavage of C3 in ischemic tissues and to what extent the potential trigger mechanisms are organ dependent - an important question which informs the development of therapies that are more selective in their ability to limit the injury, yet preserve the other functions of complement where possible. Here we consider recent evidence for each of the three major pathways of complement activation (classical, lectin, and alternative) as mediators of I/R injury, and in particular highlight the role of lectin molecules that increasingly seem to underpin the injury in different organ models and in addition reveal unusual routes of complement activation that contribute to organ damage.
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Affiliation(s)
- Conrad A. Farrar
- MRC Centre for Transplantation, Division of Transplantation Immunology and Mucosal Biology, King’s College London School of Medicine at Guy’s, King’s College and St Thomas’ HospitalsLondon, UK
| | - Elham Asgari
- MRC Centre for Transplantation, Division of Transplantation Immunology and Mucosal Biology, King’s College London School of Medicine at Guy’s, King’s College and St Thomas’ HospitalsLondon, UK
| | - Wilhelm J. Schwaeble
- Department of Infection, Immunity, and Inflammation, Leicester UniversityLeicester, UK
| | - Steven H. Sacks
- MRC Centre for Transplantation, Division of Transplantation Immunology and Mucosal Biology, King’s College London School of Medicine at Guy’s, King’s College and St Thomas’ HospitalsLondon, UK
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11
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Abstract
Complement is a part of the body's innate immune system that helps defend the host from microbial infection. It is tightly controlled by a number of cell surface and fluid-phase proteins so that under normal circumstances injury to autologous tissues is avoided. In many pathological settings, such as when the complement regulatory mechanisms are dysfunctional or overwhelmed, complement attack of autologous tissues can occur with severe, sometimes life-threatening consequences. The kidney appears to be particularly vulnerable to complement-mediated inflammatory injury and many kidney pathologies have been linked to abnormal complement activation. Clinical and experimental studies have shown that complement attack can be a primary cause in rare, genetically predisposed kidney diseases or a significant contributor to kidney injury caused by other etiological factors. Here we provide a brief review of recent advances on the activation and regulation of the complement system in kidney disease, with a particular emphasis on the relevance of complement regulatory proteins.
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Affiliation(s)
- Allison M Lesher
- Institute for Translational Medicine and Therapeutics and Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
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12
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Thurman JM, Renner B. Dynamic control of the complement system by modulated expression of regulatory proteins. J Transl Med 2011; 91:4-11. [PMID: 20921948 PMCID: PMC3109904 DOI: 10.1038/labinvest.2010.173] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The complement system serves many biological functions, including the eradication of invasive pathogens and the removal of damaged cells and immune-complexes. Uncontrolled complement activation causes injury to host cells, however, so adequate regulation of the system is essential. Control of the complement system is maintained by a group of cell surface and circulating proteins referred to as complement regulatory proteins. The expression of the cell surface complement regulatory proteins varies from tissue to tissue. Furthermore, specific cell types can upregulate or downregulate the expression of these proteins in response to a variety of signals or insults. Altered regulation of the complement regulatory proteins can have important effects on local complement activation. In some circumstances this can be beneficial, such as in the setting of certain infections. In other circumstances, however, this can be a cause of complement-mediated injury of the tissue. A full understanding of the mechanisms by which the complement system is modulated at the local level can have important implications for how we diagnose and treat a wide range of inflammatory diseases.
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Renner B, Coleman K, Goldberg R, Amura C, Holland-Neidermyer A, Pierce K, Orth HN, Molina H, Ferreira VP, Cortes C, Pangburn MK, Holers VM, Thurman JM. The complement inhibitors Crry and factor H are critical for preventing autologous complement activation on renal tubular epithelial cells. THE JOURNAL OF IMMUNOLOGY 2010; 185:3086-94. [PMID: 20675597 DOI: 10.4049/jimmunol.1000111] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Congenital and acquired deficiencies of complement regulatory proteins are associated with pathologic complement activation in several renal diseases. To elucidate the mechanisms by which renal tubular epithelial cells (TECs) control the complement system, we examined the expression of complement regulatory proteins by the cells. We found that Crry is the only membrane-bound complement regulator expressed by murine TECs, and its expression is concentrated on the basolateral surface. Consistent with the polarized localization of Crry, less complement activation was observed when the basolateral surface of TECs was exposed to serum than when the apical surface was exposed. Furthermore, greater complement activation occurred when the basolateral surface of TECs from Crry(-/-)fB(-/-) mice was exposed to normal serum compared with TECs from wild-type mice. Complement activation on the apical and basolateral surfaces was also greater when factor H, an alternative pathway regulatory protein found in serum, was blocked from interacting with the cells. Finally, we injected Crry(-/-)fB(-/-) and Crry(+/+)fB(-/-) mice with purified factor B (an essential protein of the alternative pathway). Spontaneous complement activation was seen on the tubules of Crry(-/-)fB(-/-) mice after injection with factor B, and the mice developed acute tubular injury. These studies indicate that factor H and Crry regulate complement activation on the basolateral surface of TECs and that factor H regulates complement activation on the apical surface. However, congenital deficiency of Crry or reduced expression of the protein on the basolateral surface of injured cells permits spontaneous complement activation and tubular injury.
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Affiliation(s)
- Brandon Renner
- Department of Medicine, University of Colorado Denver School of Medicine, Denver, CO 80045, USA
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Hantavirus causing hemorrhagic fever with renal syndrome enters from the apical surface and requires decay-accelerating factor (DAF/CD55). J Virol 2008; 82:4257-64. [PMID: 18305044 DOI: 10.1128/jvi.02210-07] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
The Old World hantaviruses, members of the family Bunyaviridae, cause hemorrhagic fever with renal syndrome (HFRS). Transmission to humans occurs via inhalation of aerosols contaminated with the excreta of infected rodents. The viral antigen is detectable in dendritic cells, macrophages, lymphocytes, and, most importantly, microvascular endothelial cells. However, the site and detailed mechanism of entry of HFRS-causing hantaviruses in polarized epithelial cells have not yet been defined. Therefore, this study focused on the entry of the pathogenic hantaviruses Hantaan and Puumala into African green monkey kidney epithelial cells and primary human endothelial cells. The polarized epithelial and endothelial cells were found to be susceptible to hantavirus infection exclusively from the apical surface. Treatment with phosphatidylinositol-specific phospholipase C, which removes glycosylphosphatidylinositol (GPI)-anchored proteins from the cell surface, protects cells from infection, indicating that hantaviruses require a GPI-anchored protein as a cofactor for entry. Decay-accelerating factor (DAF)/CD55 is a GPI-anchored protein of the complement regulatory system and serves as a receptor for attachment to the apical cell surface for a number of viruses. Infection was reduced by the pretreatment of hantaviral particles with human recombinant DAF. Moreover, the treatment of permissive cells with DAF-specific antibody blocked infection. These results demonstrate that the Old World hantaviruses Hantaan and Puumala enter polarized target cells from the apical site and that DAF is a critical cofactor for infection.
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15
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Kim YO, Lim SW, Li C, Kang HJ, Ahn KO, Yang HJ, Ghee JY, Kim SH, Kim JY, Choi BS, Kim J, Yang CW. Activation of intrarenal complement system in mouse model for chronic cyclosporine nephrotoxicity. Yonsei Med J 2007; 48:517-25. [PMID: 17594162 PMCID: PMC2628083 DOI: 10.3349/ymj.2007.48.3.517] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
PURPOSE Local activation of the complement system plays a role in target organ damage. The aim of our study was to investigate the influence of cyclosporine (CsA)- induced renal injury on the complement system in the kidney. MATERIALS AND METHODS Mice fed a low salt (0.01%) diet were treated with vehicle (VH, olive oil, 1 mL/kg/day) or CsA (30 mg/kg/day) for one or four weeks. Induction of chronic CsA nephrotoxicity was evaluated with renal function and histomorphology. Activation of the complement system was assessed through analysis of the expression of C3, C4d, and membrane attack complex (MAC), and the regulatory proteins, CD46 and CD55. CsA treatment induced renal dysfunction and typical morphology (tubulointerstitial inflammation and fibrosis) at four weeks. RESULTS CsA-induced renal injury was associated with increased the expression of C3, C4d, and MAC (C9 and upregulation of complement regulatory proteins (CD 46 and CD55). Immunohistochemistry revealed that the activated complement components were mainly confined to the injured tubulointerstitium. CONCLUSION CsA-induced renal injury is associated with activation of the intrarenal complement system.
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Affiliation(s)
- Young Ok Kim
- Xenotransplantation Center, Division of Nephrology, Department of Internal Medicine, The Catholic University of Korea, Seoul, Korea
| | - Sun Woo Lim
- Xenotransplantation Center, Division of Nephrology, Department of Internal Medicine, The Catholic University of Korea, Seoul, Korea
| | - Can Li
- Xenotransplantation Center, Division of Nephrology, Department of Internal Medicine, The Catholic University of Korea, Seoul, Korea
- Department of Internal Medicine, The Affiliated Hospital, YanBian University Medical College, YanJi 133000, JiLin, PR China
| | - Hee Jung Kang
- Department of Laboratory Medicine, Hallym University College of Medicine, Anyang, Korea
| | - Kyung Ohk Ahn
- Xenotransplantation Center, Division of Nephrology, Department of Internal Medicine, The Catholic University of Korea, Seoul, Korea
| | - Hyun Joo Yang
- Xenotransplantation Center, Division of Nephrology, Department of Internal Medicine, The Catholic University of Korea, Seoul, Korea
| | - Jung Yeon Ghee
- Xenotransplantation Center, Division of Nephrology, Department of Internal Medicine, The Catholic University of Korea, Seoul, Korea
| | - Su hyun Kim
- Xenotransplantation Center, Division of Nephrology, Department of Internal Medicine, The Catholic University of Korea, Seoul, Korea
| | - Jin Young Kim
- Xenotransplantation Center, Division of Nephrology, Department of Internal Medicine, The Catholic University of Korea, Seoul, Korea
| | - Bum Soon Choi
- Xenotransplantation Center, Division of Nephrology, Department of Internal Medicine, The Catholic University of Korea, Seoul, Korea
| | - Jin Kim
- Cell Death Research Center, Department of Anatomy, The Catholic University of Korea, Seoul, Korea
| | - Chul Woo Yang
- Xenotransplantation Center, Division of Nephrology, Department of Internal Medicine, The Catholic University of Korea, Seoul, Korea
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Abstract
The complement system is an important component of the innate immune system and a modulator of adaptive immunity. The entire complement system is focused on C3 and C5. Thus, there are proteins that activate C3 and C5, those that regulate this activation, and those that transduce the effects of C3 and C5 activation products; each can affect the kidney in renal injury. The normal kidney has the inherent capacity to protect itself from complement activation through cellular expression of decay-accelerating factor, membrane cofactor protein (in human beings), and Crry (in rodents). In addition, plasma factor H protects vascular spaces in the kidney. Although the main function of these proteins is to limit complement activation, there is now considerable evidence that they can transduce signals on engagement in immune cells. The G-protein-coupled 7-span transmembrane receptors for C3a and C5a, and the integral membrane complement receptors (CR) for C3b, iC3b, and C3dg, are expressed outside the kidney, particularly in cells of hematopoietic and immune lineage. These are important in renal injury through their infiltration of the kidney and/or by affecting kidney-directed immune responses. There is mounting evidence that intrinsic glomerular and tubular cell C3aR and C5aR expression and activation also can affect renal injury. CR1 on podocytes and the beta2 integrins CR3 and CR4 in kidney dendritic cells have functions that remain poorly defined. Cells of the kidney also have the capacity to produce and activate their own complement proteins. Thus, intrinsic renal cells express decay-accelerating factor, membrane cofactor protein, Crry, C3aR, C5aR, CR1, CR3, and CR4. These can be engaged by C3 and C5 activation products derived from systemic and local pools in renal injury. Given their capacity to provide signals that influence kidney cellular behavior, their activation can have substantial effects in renal injury. Defining these in a cell- and disease-specific fashion is an exciting challenge for future research.
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Affiliation(s)
- Tipu S Puri
- Section of Nephrology, University of Chicago, Chicago, IL 60637, USA
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17
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Bao L, Haas M, Minto AW, Quigg RJ. Decay-accelerating factor but not CD59 limits experimental immune-complex glomerulonephritis. J Transl Med 2007; 87:357-64. [PMID: 17259999 DOI: 10.1038/labinvest.3700522] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
The complex balance between the pro-activating and regulatory influences of the complement system can affect the pathogenesis of immune complex-mediated glomerulonephritis (ICGN). Key complement regulatory proteins include decay accelerating factor (DAF) and CD59, which inhibit C3 activation and C5b-9 generation, respectively. Both are glycosylphosphatidylinositol-linked cell membrane proteins, which are widely distributed in humans and mice. Chronic serum sickness induced by daily immunization with horse spleen apoferritin over 6 weeks was used to induce ICGN in DAF-, CD59- and DAF/CD59-deficient mice, with wild-type littermate mice serving as controls. Both DAF and DAF/CD59-deficient mice had an increased incidence of GN relative to wild-type controls associated with significantly increased glomerular C3 deposition. Disease expression in CD59-deficient mice was no different than wild-type controls. DAF- and DAF/CD59-deficient mice also had increased monocyte chemoattractant protein-1 mRNA expression and glomerular infiltration with CD45(+) leukocytes. Our findings suggest that activation of C3 is strongly associated with experimental ICGN while downstream formation of C5b-9 is of lesser pathogenic importance in this model.
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Affiliation(s)
- Lihua Bao
- Section of Nephrology, The University of Chicago, Chicago, IL 60637, USA.
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18
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Abstract
The complement system consists of 3 pathways and more than 30 proteins, including those with biological activity that directly or indirectly mediate the effects of this system, plus a set of regulatory proteins necessary to prevent injudicious complement activation on host tissue. The role for complement in the pathogenesis of systemic lupus erythematosus (SLE) is paradoxic. On one hand, the complement system appears to have protective features in that hereditary homozygous deficiencies of classic pathway components are associated with an increased risk for SLE. On the other hand, immune complex-mediated activation of complement in affected tissues is clearly evident in both experimental and human SLE along with pathologic features that are logical consequences of complement activation. By using accurate mouse models of SLE, we have gained remarkable insights into pathogenic features likely relevant to the human disease, and the ability to test potential therapies, some of which have made it to standard clinical use. Studies in genetically altered mice and using recombinant protein inhibitors of complement have confirmed what was believed but unproven-early complement proteins C1q and C4 are protective whereas complement activation later in the pathways is proinflammatory and deleterious. Two complement inhibitors, soluble complement receptor 1 (TP10, Avant Immunotherapeutics, Needham, MA) and a monoclonal anti-C5 antibody (Eculizumab, Alexion Pharmaceuticals, Inc., Cheshire, CT) have been shown to inhibit complement safely and now are being investigated in a variety of clinical conditions. Although these and others earlier in their clinical development hold promise to be used therapeutically in lupus nephritis, this optimism must be tempered by the fact that the clinical trials to prove this remain fraught with obstacles.
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Affiliation(s)
- Lihua Bao
- Section of Nephrology, Department of Medicine, University of Chicago, Chicago, IL 60637, USA.
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Moll S, Lange S, Mihatsch MJ, Dragic Z, Schifferli JA, Inal JM. CRIT is expressed on podocytes in normal human kidney and upregulated in membranous nephropathy. Kidney Int 2006; 69:1961-8. [PMID: 16598195 DOI: 10.1038/sj.ki.5000379] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Complement C2 receptor inhibitor trispanning (CRIT) is a novel human complement regulatory cell surface receptor. It binds the human complement protein C2 and blocks the classical pathway of complement activation, thus protecting the cell against complement attack. CRIT expression in the kidney was analyzed by immunohistochemistry and in situ hybridization. Normal kidney and renal biopsies of patients with different nephropathies were studied. In glomeruli, CRIT protein was expressed only in podocytes. CRIT was also detected in endothelial cells of arterioles and arteries, but not of veins and peritubular and glomerular capillaries. A homogeneous and marked upregulation of CRIT was observed in podocytes in membranous nephropathy (MN). In focal and segmental glomerulosclerosis (FSGS) and minimal change disease, CRIT was downregulated in glomeruli with a loss of the staining in sclerotic lesions of FSGS. No specific changes were observed in the other nephropathies studied. However, podocytes showed in all pathologies a redistribution of CRIT in the cell bodies of 'activated' podocytes. The intensity of mRNA transcription correlated directly with the protein staining in the normal kidney and in MN. These data indicate that CRIT is expressed in the normal human kidney essentially by glomerular podocytes and arterial endothelial cells. The podocyte CRIT expression is upregulated in MN, which is in strong contrast with the known loss of podocyte complement receptor 1. CRIT might represent the last line of defense against complement aggression in MN, and the upregulation of CRIT in 'activated' podocytes might represent a similar self-defense mechanism.
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Affiliation(s)
- S Moll
- Clinical Pathology, University Hospitals of Geneva and Lausanne, Geneva, Switzerland
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20
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Abstract
Over the last few years, dramatic increases in our knowledge about diffusely adhering Escherichia coli (DAEC) pathogenesis have taken place. The typical class of DAEC includes E. coli strains harboring AfaE-I, AfaE-II, AfaE-III, AfaE-V, Dr, Dr-II, F1845, and NFA-I adhesins (Afa/Dr DAEC); these strains (i) have an identical genetic organization and (ii) allow binding to human decay-accelerating factor (DAF) (Afa/Dr(DAF) subclass) or carcinoembryonic antigen (CEA) (Afa/Dr(CEA) subclass). The atypical class of DAEC includes two subclasses of strains; the atypical subclass 1 includes E. coli strains that express AfaE-VII, AfaE-VIII, AAF-I, AAF-II, and AAF-III adhesins, which (i) have an identical genetic organization and (ii) do not bind to human DAF, and the atypical subclass 2 includes E. coli strains that harbor Afa/Dr adhesins or others adhesins promoting diffuse adhesion, together with pathogenicity islands such as the LEE pathogenicity island (DA-EPEC). In this review, the focus is on Afa/Dr DAEC strains that have been found to be associated with urinary tract infections and with enteric infection. The review aims to provide a broad overview and update of the virulence aspects of these intriguing pathogens. Epidemiological studies, diagnostic techniques, characteristic molecular features of Afa/Dr operons, and the respective role of Afa/Dr adhesins and invasins in pathogenesis are described. Following the recognition of membrane-bound receptors, including type IV collagen, DAF, CEACAM1, CEA, and CEACAM6, by Afa/Dr adhesins, activation of signal transduction pathways leads to structural and functional injuries at brush border and junctional domains and to proinflammatory responses in polarized intestinal cells. In addition, uropathogenic Afa/Dr DAEC strains, following recognition of beta(1) integrin as a receptor, enter epithelial cells by a zipper-like, raft- and microtubule-dependent mechanism. Finally, the presence of other, unknown virulence factors and the way that an Afa/Dr DAEC strain emerges from the human intestinal microbiota as a "silent pathogen" are discussed.
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Affiliation(s)
- Alain L Servin
- Institut National de la Santé et de la Recherche Médicale, Unité 510, Faculté de Pharmacie Paris XI, Châtenay-Malabry, France.
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Gherghiceanu M, Penescu M, Mandache E. The predictive value of peritubular capillaries C3d deposition in IgA glomerulonephritis. J Cell Mol Med 2005; 9:143-52. [PMID: 15784172 PMCID: PMC6741313 DOI: 10.1111/j.1582-4934.2005.tb00344.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The IgA glomerulonephritis (IgAGN) is one of the most common primary glomerulonephritis and has a variable and difficult to predict evolution toward the end-stage nephrosclerosis. The deposition of C3d complement component in peritubular capillaries (PTCs) indicates a variant type of acute rejection while C3d deposition in primary glomerulonephritis (GN) is poorly documented. The aim of this study is to examine C3d expression in peritubular capillaries (PTCs) as a predictive marker and its correlation with the severity of renal injury in IgA glomerulonephritis. Polyclonal FITC conjugated rabbit anti-human C3c and C3d antibodies were used for direct immunofluorescent evaluation of the C3c and C3d deposits in 24 kidney biopsies with IgA glomerulonephritis. The study revealed that the C3d deposits in peritubular capillaries were associated with known predictors for rapid progression of IgAGN: glomerular sclerosis (63.6%), atrophic tubules (90.9%) and interstitial sclerosis (81.8%). The intensity of the C3c glomerular immunofluorescent deposits was related with active lesions. Thus, the predictive value of C3d deposition on PTCs in IgAGN is worth to be taken into consideration as an unfavorable outcome of the disease and request further long run investigations.
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Affiliation(s)
- Mihaela Gherghiceanu
- Ultrastructural Pathology Laboratory, "Babes" National Institute of Pathology, Bucharest 050096, Romania.
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22
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Abstract
Our body is in constant interaction with the environment. Some of the interactions involve the recognition and disposal of foreign substances that may harm the delicate balance between health and disease. The foreign elements, or antigens, include infectious organisms and lifeless macromolecules. The ability of the body to recognize what is dangerous and what is inconsequential, and to refrain from damaging what is perceived as self, are the main functions of the immune system. One important component of the innate immune response is the complement system. This article describes the different mechanisms of how complement is activated and the consequence of this activation, followed by a characterization of the complement's role in inflammation and autoimmunity, and the therapeutic considerations emanating from these studies.
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Affiliation(s)
- Hector Molina
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, Box 8045, CSRB 6604, 4940 Parkview Place, St. Louis, MO 63110, USA.
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Vongwiwatana A, Tasanarong A, Hidalgo LG, Halloran PF. The role of B cells and alloantibody in the host response to human organ allografts. Immunol Rev 2003; 196:197-218. [PMID: 14617206 DOI: 10.1046/j.1600-065x.2003.00093.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Some human organ transplants deteriorate slowly over a period of years, often developing characteristic syndromes: transplant glomerulopathy (TG) in kidneys, bronchiolitis obliterans in lungs, and coronary artery disease in hearts. In the past, we attributed late graft deterioration to "chronic rejection", a distinct but mysterious immunologic process different from conventional rejection. However, it is likely that much of chronic rejection is explained by conventional T-cell-mediated rejection (TMR), antibody-mediated rejection (AMR), and other insults. Recently, criteria have emerged to now permit us to diagnose AMR in kidney transplants, particularly C4d deposition in peritubular capillaries and circulating antibody against donor human leukocyte antigens (HLA). Some cases with AMR develop TG, although the relationship of TG to AMR is complex. Thus, a specific diagnosis of AMR in kidney can now be made, based on graft damage, C4d deposition, and donor-specific alloantibodies. Criteria for AMR in other organs must be defined. Not all late rejections are AMR; some deteriorating organs probably have smoldering TMR. The diagnosis of late ongoing AMR raises the possibility of treatment to suppress the alloantibody, but efficacy of the available treatments requires further study.
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Affiliation(s)
- Attapong Vongwiwatana
- Department of Medicine, Division of Nephrology & Transplantation Immunology, University of Alberta, 250 Heritage Medical Research Center, Edmonton, Alberta, Canada T6G 2S2
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24
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Abstract
The role of innate immunity in allograft injury is just beginning to become clear, and complement is probably one of a number of factors that are activated very early in the course of transplantation. Kidney transplantation into complement-inhibited rats reduces subsequent inflammation of the graft, probably as a result of reduction of ischemia reperfusion damage as well as diminution of immune mediated damage. Closer analysis of the role of locally synthesised components in mice has suggested that regional synthesis of complement proteins, in particular by the renal tubule, may play a more important role than circulating components. A marked effect on the antidonor T cell response may be explained by the triggering of complement receptors present on antigen presenting cells or T cells infiltrating the graft, or by a more direct effect of complement on the liaison between proximal tubule cells and T cells. Therapeutic control is likely to require a shift to a more targeted approach, directed at complement components produced in the extravascular tissue compartment.
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Affiliation(s)
- Steven H Sacks
- Guy's Hospital, King's College, London, Nephrology and Transplantation, London, United Kingdom.
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25
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Bao L, Spiller OB, St John PL, Haas M, Hack BK, Ren G, Cunningham PN, Doshi M, Abrahamson DR, Morgan BP, Quigg RJ. Decay-accelerating factor expression in the rat kidney is restricted to the apical surface of podocytes. Kidney Int 2002; 62:2010-21. [PMID: 12427125 DOI: 10.1046/j.1523-1755.2002.t01-1-00652.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Decay-accelerating factor (DAF) has inhibitory activity toward complement C3 and C5 convertases. DAF is present in human glomeruli and on cultured human glomerular visceral epithelial cells (GEC). We studied the distribution and function of rat DAF. METHODS Function-neutralizing antibodies (Abs) were raised against DAF. The distribution of DAF in vivo was determined by immunoelectron microscopy. Functional studies were performed in cultured GEC and following IV injection of anti-DAF Abs into rats. RESULTS DAF was present exclusively on the apical surfaces of GEC, and was not present on the basal surfaces of GEC, nor other glomerular or kidney cells. DAF was functionally active on cultured GEC, and served to limit complement activation in concert with CD59, an inhibitor of C5b-9 formation. Upon injection into normal rats, anti-DAF F(ab')2 Abs bound to GEC in vivo, yet there was no evidence for complement activation and animals did not develop abnormal albuminuria. Anti-megalin complement-activating IgG Abs were "planted" on GEC, which activated complement as evidenced by the presence of C3d on GEC. Attempts to inhibit DAF function with anti-DAF Abs did not affect the quantity of complement activation by these anti-megalin Abs, nor did it lead to development of abnormal albuminuria. In contrast, in the puromycin aminonucleoside model of GEC injury and proteinuria, anti-DAF Abs slowed the recovery from renal failure that occurs in this model. CONCLUSION In cultured rat GEC, DAF is an effective complement regulator. In vivo, DAF is present on GEC apical surfaces. Yet, it appears that DAF is not essential to prevent complement activation from occurring under normal circumstances and in those cases in which complement-activating Abs are present on the basal surfaces of GEC in vivo. However, in proteinuric conditions, DAF appears to be protective to GEC.
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Affiliation(s)
- Lihua Bao
- Section of Nephrology, The University of Chicago, Chicago, Illinois 60637, USA.
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26
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Neary JJ, Conlon PJ, Croke D, Dorman A, Keogan M, Zhang FY, Vance JM, Pericak-Vance MA, Scott WK, Winn MP. Linkage of a gene causing familial membranoproliferative glomerulonephritis type III to chromosome 1. J Am Soc Nephrol 2002; 13:2052-7. [PMID: 12138136 DOI: 10.1097/01.asn.0000022006.49966.f8] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Membranoproliferative glomerulonephritis (MPGN) type III is a chronic progressive renal disease of unknown cause. The diagnosis is based on renal pathologic features (specifically immunofluorescence staining patterns and ultrastructural appearance). Mesangial cell proliferation and subendothelial and subepithelial deposits characterize the renal disease. Although the actual prevalence of this disease is not known, the disease is rare and usually sporadic. The clinical features of MPGN include the nephrotic syndrome and hematuria, with renal dysfunction occurring in approximately 50% of patients. Progression to end-stage renal disease is variable, and some patients exhibit stabilization or even improvement. Here is presented an Irish family in which there are eight affected members in four generations, suggesting autosomal dominant inheritance. This is the only reported family with an inherited form of MPGN type III. To evaluate the disease in this family, a genome-wide scan was performed with a panel of 402 polymorphic microsatellite markers, defining a grid with an average resolution of 10 cM (centimorgans). Significant evidence for linkage was observed on chromosome 1q31-32, with a maximal logarithm of the odds score of 3.86 at theta = 0.00 for microsatellite marker GATA135F02. Recombination events among affected individuals, as detected by haplotype analysis, established a 22-cM minimal candidate region flanked by markers D1S3470 and GATA124F08. The data provide evidence for a gene for familial MPGN on chromosome 1q.
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Affiliation(s)
- John J Neary
- Departments of Nephrology, Beaumont Hospital, Dublin, Ireland
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27
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Bardenstein DS, Cheyer CJ, Lee C, Cocuzzi E, Mizuno M, Okada N, Medof ME. Blockage of complement regulators in the conjunctiva and within the eye leads to massive inflammation and iritis. Immunology 2001; 104:423-30. [PMID: 11899428 PMCID: PMC1783320 DOI: 10.1046/j.1365-2567.2001.01316.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The open environment of the eye is continuously subject to an influx of foreign agents that can activate complement. Decay-accelerating factor (DAF), membrane cofactor protein (MCP) and CD59 are regulators that protect self-cells from autologous complement activation on their surfaces. They are expressed in the eye at unusually high levels but their physiological importance in this site is unstudied. In the rat, a structural analogue termed 5I2 antigen (5I2 Ag) has actions overlapping DAF and MCP. In this investigation, we injected F(ab')2 fragments of 5I2 mAb into the conjunctiva and aqueous humor, in the latter case with and without concomitant blockage of CD59. Massive neutrophilic infiltration of the stroma and iris resulted upon blocking 5I2 Ag activity. Frank necrosis of the iris occurred upon concomitant intraocular blockage of CD59. C3b was identified immunohistochemically, and minimal effects were seen in complement-depleted animals and in those treated with non-relevant antibody. The finding that blockage of 5I2 Ag function in periocular tissues and within the eye causes intense conjunctival inflammation and iritis demonstrates the importance of intrinsic complement regulators in protecting ocular tissues from spontaneous or bystander attack by autologous complement.
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Affiliation(s)
- D S Bardenstein
- Institute of Pathology, Center for Vision Research, Case Western Reserve University School of Medicine, Cleveland, OH, USA
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28
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Sekine H, Reilly CM, Molano ID, Garnier G, Circolo A, Ruiz P, Holers VM, Boackle SA, Gilkeson GS. Complement component C3 is not required for full expression of immune complex glomerulonephritis in MRL/lpr mice. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 166:6444-51. [PMID: 11342671 DOI: 10.4049/jimmunol.166.10.6444] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Complement activation and tissue deposition of complement fragments occur during disease progression in lupus nephritis. Genetic deficiency of some complement components (e.g., Factor B) and infusion of complement inhibitors (e.g., Crry, anti-C5 Ab) protect against inflammatory renal disease. Paradoxically, genetic deficiencies of early components of the classical complement pathway (e.g., C1q, C4, and C2) are associated with an increased incidence of lupus in humans and lupus-like disease in murine knockout strains. Complement protein C3 is the converging point for activation of all three complement pathways and thus plays a critical role in biologic processes mediated by complement activation. To define the role of C3 in lupus nephritis, mice rendered C3 deficient by targeted deletion were backcrossed for eight generations to MRL/lpr mice, a mouse strain that spontaneously develops lupus-like disease. We derived homozygous knockout (C3(-/-)), heterozygous (C3(+/-)), and C3 wild-type (C3(+/+)) MRL/lpr mice. Serum levels of autoantibodies and circulating immune complexes were similar among the three groups. However, there was earlier and significantly greater albuminuria in the C3(-/-) mice compared with the other two groups. Glomerular IgG deposition was also significantly greater in the C3(-/-) mice than in the other two groups, although overall pathologic renal scores were similar. These results indicate that C3 and/or activation of C3 is not required for full expression of immune complex renal disease in MRL/lpr mice and may in fact play a beneficial role via clearance of immune complexes.
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Affiliation(s)
- H Sekine
- Department of Medicine, Medical University of South Carolina and the Medical Research Service, Ralph H. Johnson Veterans Affairs Medical Center, Charleston, SC 29425, USA
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29
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Abstract
During the past decade, research has shown that the kidney has the capacity to synthesize most of the activation pathway components of the complement cascade. As well as implying physiological roles in local clearance of immune complexes and defense against invasive organisms, an increasing amount of evidence indicates that the intrarenal synthesis of complement makes an important contribution in the pathogenesis of renal injury. Here we review this evidence and present a case for more definitive investigation of these functions.
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Affiliation(s)
- W Zhou
- Department of Nephrology and Transplantation, Guy's Hospital, London, England, United Kingdom
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30
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Mason JC, Lidington EA, Yarwood H, Lublin DM, Haskard DO. Induction of endothelial cell decay-accelerating factor by vascular endothelial growth factor: a mechanism for cytoprotection against complement-mediated injury during inflammatory angiogenesis. ARTHRITIS AND RHEUMATISM 2001; 44:138-50. [PMID: 11212152 DOI: 10.1002/1529-0131(200101)44:1<138::aid-anr18>3.0.co;2-g] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE Decay-accelerating factor (DAF) is a widely expressed, multifunctional cell surface protein involved in complement regulation and cell signaling. Previous studies have demonstrated that endothelial cell (EC) DAF is up-regulated by tumor necrosis factor alpha and inhibits complement binding. Because vascular endothelial growth factor (VEGF) is cytoprotective to endothelium and is expressed at sites of chronic inflammation, we hypothesized that VEGF may induce DAF expression during inflammatory angiogenesis. METHODS Human umbilical vein and dermal microvascular EC were isolated using routine procedures, and the regulation and function of DAF, as well as other complement-regulatory proteins (membrane cofactor protein and CD59), were analyzed following stimulation with VEGF. RESULTS Incubation of large- or small-vessel EC with VEGF led to increased expression of DAF, with maximal expression after 48-72 hours of stimulation. This effect depended on the activation of protein kinase C (PKC) and required increased steady-state messenger RNA levels and de novo protein synthesis. Although VEGF-induced EC proliferation was inhibited by both p38 and p42/44 mitogen-activated protein kinase (MAPK) antagonists, DAF up-regulation in response to VEGF was only sensitive to inhibition of p38 MAPK. VEGF-stimulated EC showed a 60% reduction in C3 deposition following complement activation, and this resulted in a marked reduction in complement-mediated EC lysis. These protective effects were abolished by anti-DAF monoclonal antibody 1H4. CONCLUSION This study confirms the importance of PKC for the regulation of DAF expression by EC and reveals VEGF to be a physiologic agonist for this pathway. The up-regulation of DAF expression by VEGF may represent an important mechanism for the protection of EC from complement-mediated injury during angiogenesis in inflammatory rheumatic diseases.
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Affiliation(s)
- J C Mason
- The BHF Cardiovascular Medicine Unit, Imperial College School of Science, Technology, and Medicine, Hammersmith Hospital, London, UK
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31
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Szczotka LB, Cocuzzi E, Medof ME. Decay-accelerating factor in tears of contact lens wearers and patients with contact lens-associated complications. Optom Vis Sci 2000; 77:586-91. [PMID: 11138832 DOI: 10.1097/00006324-200011000-00008] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
PURPOSE Complement activation fragments have been detected in the anterior segment during 1) eye closure, 2) contact lens wear, and 3) in some contact lens-associated pathologies. The decay-accelerating factor (DAF), a membrane-associated complement regulatory protein that inhibits the central C3 amplification convertases of the cascade, is present on both the ocular surface and in tears. In this study, we measured levels of tear DAF in asymptomatic contact lens patients and in patients who presented with contact lens-associated complications. METHODS Tears were collected from 55 patients using capillary pipettes. Subjects included normal non-contact lens wearing controls (N = 14), asymptomatic soft (N = 13) and rigid gas permeable (N = 5) wearers, and individuals with contact lens-induced acute red eye (CLARE) (N = 4), ulcerative keratitis (N = 3), giant papillary conjunctivitis (GPC) (N = 8), contact lens peripheral ulcers (N = 3), and infiltrative keratitis (N = 5). Levels of DAF were assessed using a two-site immunoradiometric assay using anti-DAF monoclonal antibodies. RESULTS The mean concentration of DAF in normal controls was found to be 149+/-78 ng/ml, 117+/-59 ng/ml, and 111+/-86 ng/ml for noncontact lens patients, and asymptomatic soft and rigid gas permeable lens wearers, respectively. In the conditions of CLARE, infiltrative keratitis, and GPC, DAF concentrations were significantly reduced compared with normal noncontact lens controls. Compared with asymptomatic soft lens patients, the condition of infiltrative keratitis showed a significant reduction in tear DAF. CONCLUSIONS This study documents a trend toward decreased levels of tear DAF in patients with the contact lens associated inflammatory conditions CLARE, GPC, and infiltrative keratitis. Tears of patients with infiltrates show the most significant reduction of tear DAF. The reductions may be associated with enhanced complement activation contributing to the pathogeneses of infiltrative keratitis and associated ocular surface diseases.
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Affiliation(s)
- L B Szczotka
- Center For Vision Research, Case Western Reserve University, Cleveland, Ohio, USA.
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32
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Arora M, Arora R, Tiwari SC, Das N, Srivastava LM. Expression of complement regulatory proteins in diffuse proliferative glomerulonephritis. Lupus 2000; 9:127-31. [PMID: 10787010 DOI: 10.1191/096120300678828154] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
This study assessed the expression of complement receptor 1 (CR1), decay accelerating factor (DAF) and membrane inhibitor of reactive lysis (CD59) on the erythrocytes and glomerulus of diffuse proliferative glomerulonephritis (DPGN) of systemic lupus erythematosus (SLE) patients using flow cytometry and immunofluorescence techniques to elucidate their role in the pathogenesis of DPGN. Expression of CR1 on the erythrocytes and glomerulus of DPGN patients was reduced compared with expression in normal subjects. However, expression of DAF and CD59 was increased on both erythrocytes and glomerulus of DPGN patients, suggesting the generation of a protective response against complement-mediated injury.
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Affiliation(s)
- M Arora
- Department of Biochemistry, All India Institute of Medical Sciences, New Delhi.
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33
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Collins AB, Schneeberger EE, Pascual MA, Saidman SL, Williams WW, Tolkoff-Rubin N, Cosimi AB, Colvin RB. Complement activation in acute humoral renal allograft rejection: diagnostic significance of C4d deposits in peritubular capillaries. J Am Soc Nephrol 1999; 10:2208-14. [PMID: 10505698 DOI: 10.1681/asn.v10102208] [Citation(s) in RCA: 383] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
The distinction between acute humoral rejection (AHR) and acute cellular rejection (ACR) in renal allografts is therapeutically important, but pathologically difficult. Since AHR is probably mediated by antibodies to the donor endothelium that activate the classical complement pathway, it was hypothesized that peritubular capillary C4d deposition might distinguish this group. Renal biopsies (n = 16) from 10 patients with AHR who had acute graft dysfunction, neutrophils in peritubular capillaries, and a concurrent positive cross-match were stained for C4d by immunofluorescence. Control biopsies for comparison showed ACR (n = 14), cyclosporin A toxicity (n = 6), or no abnormality (n = 4). Peribiopsy sera were tested for anti-donor HLA antibody. C4d deposited prominently and diffusely in the peritubular capillaries in all AHR biopsies (16 of 16). IgM and/or C3 were also present in 19 and 44%, respectively. With two-color immunofluorescence, C4d was localized in basement membranes (type IV collagen+) and in the endothelium (Ulex europaeus agglutinin-I+). In ACR, no more than trace C4d was found in peritubular capillaries (P < 0.0001 versus AHR), and no patient had anti-donor HLA antibodies (0 of 8); 27% had neutrophils in peritubular capillaries. One of six biopsies with cyclosporin A toxicity had similar C4d deposits, and circulating anti-donor class I antibody was detected. Grafts with AHR were lost (40%) more often than those with ACR (0%; P < 0.02). C4d in peritubular capillary walls distinguishes AHR from ACR, is more specific and sensitive than traditional criteria, and is a potentially valuable adjunct in the diagnosis of graft dysfunction.
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Affiliation(s)
- A B Collins
- Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston 02114, USA
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Induction of Decay-Accelerating Factor by Cytokines or the Membrane-Attack Complex Protects Vascular Endothelial Cells Against Complement Deposition. Blood 1999. [DOI: 10.1182/blood.v94.5.1673.417a05_1673_1682] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Vascular endothelium is continuously exposed to complement-mediated challenge, and this is enhanced during inflammation. Although the complement-regulatory proteins decay-accelerating factor (DAF), CD59, and membrane cofactor protein (MCP) protect endothelial cells (ECs) against complement-mediated injury, the control of their expression and relative contributions to vascular protection is unclear. We explored the hypothesis that mechanisms exist which induce upregulation of complement-regulatory proteins on ECs to maintain vascular function in inflammation. Tumor necrosis factor alpha (TNF) and interferon gamma (IFNγ) each increased DAF expression but not CD59 or MCP expression, and a combination of these cytokines was more potent than either alone. Cytokine-induced expression depended on increased DAF mRNA and de novo protein synthesis and was maximal by 72 hours. In addition, assembly of the membrane-attack complex (MAC) on ECs induced a 3-fold increase in DAF expression, and this was enhanced by cytokines. DAF upregulation was not inhibited by protein kinase C (PKC) antagonists. The increase in DAF was functionally relevant since it reduced complement 3 (C3) deposition by 40%, and this was inhibited by an anti-DAF monoclonal antibody. These observations indicate that upregulation of DAF expression by cytokines or MAC may represent an important feedback mechanism to maintain the integrity of the microvasculature during subacute and chronic inflammatory processes involving complement activation.
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Induction of Decay-Accelerating Factor by Cytokines or the Membrane-Attack Complex Protects Vascular Endothelial Cells Against Complement Deposition. Blood 1999. [DOI: 10.1182/blood.v94.5.1673] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractVascular endothelium is continuously exposed to complement-mediated challenge, and this is enhanced during inflammation. Although the complement-regulatory proteins decay-accelerating factor (DAF), CD59, and membrane cofactor protein (MCP) protect endothelial cells (ECs) against complement-mediated injury, the control of their expression and relative contributions to vascular protection is unclear. We explored the hypothesis that mechanisms exist which induce upregulation of complement-regulatory proteins on ECs to maintain vascular function in inflammation. Tumor necrosis factor alpha (TNF) and interferon gamma (IFNγ) each increased DAF expression but not CD59 or MCP expression, and a combination of these cytokines was more potent than either alone. Cytokine-induced expression depended on increased DAF mRNA and de novo protein synthesis and was maximal by 72 hours. In addition, assembly of the membrane-attack complex (MAC) on ECs induced a 3-fold increase in DAF expression, and this was enhanced by cytokines. DAF upregulation was not inhibited by protein kinase C (PKC) antagonists. The increase in DAF was functionally relevant since it reduced complement 3 (C3) deposition by 40%, and this was inhibited by an anti-DAF monoclonal antibody. These observations indicate that upregulation of DAF expression by cytokines or MAC may represent an important feedback mechanism to maintain the integrity of the microvasculature during subacute and chronic inflammatory processes involving complement activation.
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Behr TM, Feucht HE, Richter K, Reiter C, Spes CH, Pongratz D, Uberfuhr P, Meiser B, Theisen K, Angermann CE. Detection of humoral rejection in human cardiac allografts by assessing the capillary deposition of complement fragment C4d in endomyocardial biopsies. J Heart Lung Transplant 1999; 18:904-12. [PMID: 10528753 DOI: 10.1016/s1053-2498(99)00043-1] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND There are no well-established diagnostic criteria to detect humoral rejection in organ transplantation. The value of commonly used markers in immunohistochemistry, such as C1q, C3c, IgG, IgM and fibrinogen, is questioned by some groups. Complement fragment C4d is a more stable marker of complement activation as it is covalently bound to graft capillaries. C4d has been shown to identify clinically relevant, but otherwise undetectable humoral anti-graft reactions in human kidney transplants. METHODS Immunohistochemical techniques were used to evaluate 155 endomyocardial biopsies from 56 heart transplant recipients less than 3 months post transplantation for the presence of capillary C4d staining. In a subset of patients, C4d staining was compared with C1q, C3c, IgM and fibrin staining and was correlated with clinical outcome. RESULTS Within 3 months 9 of 56 patients died. Five of these nonsurvivors had prominent C4d staining (p < .05), whereas C1q, C3c and IgM showed no correlation with clinical outcome. Presence of fibrin correlated with clinical outcome and C4d staining (p < .05). CONCLUSIONS The capillary deposition of complement split product C4d in human endomyocardial biopsies was significantly associated with graft loss. Determination of fibrin deposition may yield additional information to establish a diagnosis of humoral rejection. The immunohistochemical assessment of capillary deposition of C4d and fibrin appears to be an appropriate tool for the identification of patients, who may require additional or alternative immunosuppressive therapy targeted against the humoral immune system.
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Affiliation(s)
- T M Behr
- Department of Cardiology, Klinikum Innenstadt, Munich, Germany
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37
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Abstract
In humans, decay-accelerating factor (DAF) is a widely distributed, cell-bound inhibitor of the complement activation enzymes and plays a key role in regulating complement activation, preventing the generation of anaphylotoxins and opsonins, and protecting against complement-mediated lysis. Rodent analogues of DAF have recently been identified, providing a new avenue for the analysis of function. Rat DAF was cloned in our laboratory. Here we describe the generation of monoclonal antibodies (mAbs) against rat DAF, using transfected cells as immunogen, and their use in the analysis of the distribution of DAF in the rat by flow cytometry, Western blot analysis and immunohistochemistry. One of the mAbs was found to block the complement inhibitory function of rat DAF, offering the prospect of neutralization of DAF function in vivo. The antibodies have also been used for purification of DAF from rat erythrocytes by affinity chromatography. Rat DAF purified in this manner was similar in molecular mass to human DAF. The purified protein incorporated into lipid membranes, confirming the presence of a glycolipid anchor, and incorporated protein strongly inhibited the rat C3 convertase. Rat DAF was strongly expressed on endothelia throughout the animal and was also present in most tissues and organs. DAF expression was weak or absent in the brain and on circulating and spleen-resident T cells. Strong DAF expression observed in the kidney was restricted to the glomerulus and Bowman's capsule. DAF expression in the testis was found only in association with the later stages of spermatogenesis.
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Affiliation(s)
- O B Spiller
- Complement Biology Group, Department of Medical Biochemistry, University of Wales College of Medicine, Cardiff, UK
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Abstract
The balance between local offense factors and defense machinery determines the fate of tissue injury: progression or resolution. In glomerular research, the most interest has been on the offensive side, for example, the roles of leukocytes, platelets, complement, cytokines, eicosanoids, and oxygen radical intermediates. There has been little focus on the defensive side, which is responsible for the attenuation and resolution of disease. The aim of this review is to address possible mechanisms of local defense that may be exerted during glomerular injury. Cytokine inhibitors, proteinase inhibitors, complement regulatory proteins, anti-inflammatory cytokines, anti-inflammatory eicosanoids, antithrombotic molecules, and extracellular matrix proteins can participate in the extracellular and/or cell surface defense. Heat shock proteins, antioxidants, protein phosphatases, and cyclin kinase inhibitors may contribute to the intracellular defense. This article outlines how the glomerulus, when faced with injurious cells or exposed to pathogenic mediators, defends itself via the intrinsic machinery that is brought into play in resident glomerular cells.
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Affiliation(s)
- M Kitamura
- Department of Medicine, University College London Medical School, England, United Kingdom.
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39
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Complement-mediated renal injury: Mechanisms and role of membrane regulators of complement. Clin Exp Nephrol 1998. [DOI: 10.1007/bf02480454] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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40
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Abstract
Complement deposition in the injured kidney is common, especially in glomerulonephritis. The precise role of the complement system in the mediation of tissue injury in the kidney has been defined in recent years, and this has assumed extra importance with the recent development of specific forms of therapy directed at the complement pathway. As well as the induction of cell lysis, complement has many subtle effects on cell biology, particularly on endothelial cells. Complement components are produced locally in the kidney. Detailed studies of certain rare forms of nephritis have provided evidence that complement activation can directly cause tissue injury. Appreciation of the importance of complement in hyperacute rejection of xenotransplants has given new impetus to the development of complement inhibitors. A narrative review is provided, with a brief overview of the complement pathway and its regulatory mechanisms, mechanisms of complement-induced tissue injury, local complement production, and the renal consequences of complement dysregulation. Currently available forms of therapy aimed at the complement system are reviewed, and possible future therapeutic strategies are suggested. The complement system plays a direct causal role in tissue injury in certain forms of renal disease. Specific forms of therapy are becoming available that can selectively interrupt complement activation or promote its regulation. Much of the drive for the development of these therapies comes from the field of xenotransplantation, but these forms of therapy should also be tested in various primary renal diseases.
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Affiliation(s)
- P W Mathieson
- Academic Renal Unit, University of Bristol, Bristol, England, United Kingdom.
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41
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Abstract
Complement activation plays a critical role in the pathogenesis of many forms of glomerulonephritis. Complement activation leads to tissue injury through various mechanisms including the generation of chemotactic factors and activation of the resident glomerular cells following C5b-9 insertion. Recent advances have disclosed the mechanisms of regulation of complement activation by discovery of a number of complement regulatory proteins. Decay accelerating factor (DAF), membrane cofactor protein (MCP), and complement receptor type 1 (CR1) act by inactivating C3/C5 convertase. They belong to the gene superfamily known as the regulators of complement activation (RCA), and share a common structural motif called a short consensus repeat (SCR). In contrast, CD59 works by inhibiting formation of C5b-9. The glomerulus is particularly well endowed with these membrane-bound complement regulatory proteins. DAF, MCP, and CD59 are ubiquitously expressed by all three resident glomerular cells, while CR1 is localized exclusively in podocytes. Expression of complement regulatory proteins can be changed by many factors including complement attack itself, and their expression levels are affected in various glomerular disorders. Studies utilizing cultured glomerular cells and animal models of glomerular diseases suggest important protective roles of complement regulatory proteins against immune-mediated renal injury. Recent progress in molecular biological techniques has made new therapeutic strategy feasible. Systemic administration of soluble recombinant complement regulatory proteins and local overexpression of complement regulatory proteins are promising therapeutic approaches.
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Affiliation(s)
- M Nangaku
- Division of Nephrology and Endocrinology, University of Tokyo School of Medicine, Tokyo, Japan.
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Abe K, Miyazaki M, Koji T, Furusu A, Ozono Y, Harada T, Sakai H, Nakane PK, Kohno S. Expression of decay accelerating factor mRNA and complement C3 mRNA in human diseased kidney. Kidney Int 1998; 54:120-30. [PMID: 9648070 DOI: 10.1046/j.1523-1755.1998.00961.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Decay accelerating factor (DAF), a product of mesangial cells in vitro, is expressed on the surface of cells and is a candidate for the focal suppression of complement activation. It is not clear at present whether the levels of expression of DAF and intrarenal C3 synthesis correlate with the level of tissue injury. METHODS Immunohistochemistry for DAF and C3 and nonradioactive in situ hybridization with digoxigenin-labeled oligonucleotide probe for DAF and C3 mRNA were performed in 22 tissue samples of kidneys from patients with IgA nephropathy (IgAN), 6 with membranous nephropathy (MN), 6 with lupus nephritis (LN), and five normal kidneys. RESULTS In the normal kidney, DAF was confined to the juxtaglomerular apparatus and little or no C3 was detected; however, a few glomerular cells were positive for DAF mRNA but no C3 mRNA positive cells were detected. In diseased kidneys, DAF and C3 as well as their mRNAs were detected in mesangial cells, tubular cells and infiltrating cells. Glomerular epithelial cells and Bowman's capsule cells contained little or no DAF and C3 but were positive for their mRNAs. The mean percentages of mesangial cells positive for DAF and C3 mRNAs were 49.3 +/- 11.5% and 50.7 +/- 10.3% in IgAN, and 17.0 +/- 6.3% and 19.4 +/- 9.0% in MN, respectively. The percentage of mesangial cells positive for DAF and C3 mRNAs among intraglomerular cells correlated positively with the degree of mesangial proliferation and glomerular sclerosis in IgAN. In contrast, in LN the percentage of glomerular cells positive for DAF mRNA correlated negatively with the degree of glomerular injury, while the percentage of cells positive for C3 mRNA did not change with the progression of the disease. The ratio of C3 mRNA/DAF mRNA of glomerular cells correlated with the degree of glomerular injury in both IgAN and LN. In the tubulointerstitium, the percentage of cells expressing mRNA, and C3 mRNA/DAF mRNA radio correlated with the degree of tubular atrophy and interstitial broadening in both IgAN and LN. CONCLUSIONS We conclude that DAF and C3 mRNAs are synthesized in human diseased kidneys, and that a balance between locally synthesized DAF and C3 may be important in the progression of glomerulonephritis.
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Affiliation(s)
- K Abe
- Second Department of Internal Medicine, Nagasaki University School of Medicine, Japan
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Wilmer WA, Kaumaya PT, Ember JA, Cosio FG. Receptors for the Anaphylatoxin C5a (CD88) on Human Mesangial Cells. THE JOURNAL OF IMMUNOLOGY 1998. [DOI: 10.4049/jimmunol.160.11.5646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
In these studies, we determined whether there are receptors for the anaphylatoxin C5a (C5aR, CD88) on human mesangial cells (HMC). To prepare Abs to C5aR, we first synthesized an immunogenic peptide spanning residues 8–32 of the molecule, and this peptide was used to immunize rabbits. Anti-C5aR antiserum, but not preimmune serum, stained fixed and unfixed HMC in culture. By Western blotting anti-C5aR, Abs identified a 49.6-kDa protein in HMC. By reverse-transcription PCR, a cDNA product of 558 bp was amplified corresponding to the expected size of C5aR cDNA. A cDNA of the same size was amplified simultaneously from human PBL. Restriction mapping of the products amplified from HMC and from PBL gave restriction fragments of the same size. Incubation of HMC with increasing doses of C5a caused a progressive increase in the levels of the transcription factors activator protein-1 (AP-1) and cAMP response element binding protein (CREB), but C5a had no effect on the level of nuclear factor-κB (NF-κB). The effects of C5a on AP-1 were concentration and time dependent and peaked after 60 min. In contrast, the C5a metabolite C5adesArg had no significant effect on AP-1 levels. Preincubation of HMC with rabbit anti-C5aR antiserum inhibited partially the effect of C5a on AP-1. However, anti-C5aR Abs alone had no appreciable effects on AP-1. C5a caused a significant up-regulation of mRNA for the early response genes c-jun and c-fos on HMC. These results provide evidence for the presence of C5aR in adult HMC in culture and indicate that, after binding to C5aR, the anaphylatoxin C5a causes significant up-regulation of certain transcription factors and early response genes.
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Affiliation(s)
- W. A. Wilmer
- *Department of Internal Medicine, Division of Nephrology, and
| | - P. T. Kaumaya
- †Department of Microbiology and Medical Biochemistry, The Ohio State University, Columbus, OH 43210; and
| | - J. A. Ember
- ‡The Scripps Research Institute, La Jolla, CA 92037
| | - F. G. Cosio
- *Department of Internal Medicine, Division of Nephrology, and
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Tamano M, Ohi H. Evaluation of urinary decay accelerating factor and CD59 in renal damage. Clin Exp Nephrol 1998. [DOI: 10.1007/bf02479938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Feucht HE, Opelz G. The humoral immune response towards HLA class II determinants in renal transplantation. Kidney Int 1996; 50:1464-75. [PMID: 8914011 DOI: 10.1038/ki.1996.460] [Citation(s) in RCA: 107] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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46
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Ootaka T, Saito T, Soma J, Yusa A, Abe K. Intercellular adhesion molecule-1/leukocyte function associated antigen-1-mediated and complement receptor type 4-mediated infiltration and activation of glomerular immune cells in immunoglobulin A nephropathy. Am J Kidney Dis 1996; 28:40-6. [PMID: 8712220 DOI: 10.1016/s0272-6386(96)90128-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Glomerular expression of intercellular adhesion molecule-1 (ICAM1) (CD54) and membrane cofactor protein (MCP; CD46) and positive infiltrating cells in leukocyte function associated antigen-1 (LFA1)alpha (CD11a) and C3bi receptors (CR3/CD11b, CR4/CD11c) were examined by the indirect immunoperoxidase method on 43 sets of repeated renal biopsy specimens from patients with immunoglobulin A nephropathy. Twenty-four-hour urine protein at the time of renal biopsy was also evaluated. Glomerular infiltration of LFA1alpha+ cells was significantly correlated with glomerular expression of ICAM1 (r = 0.494, P < 0.0001). Glomerular complement receptor type 4 (CR4)+ cells were significantly correlated with glomerular expression of MCP (r = 0.405, P < 0.0001). The glomerular expressions of ICAM1 and MCP were significantly correlated with each other (r = 0.700, P < 0.00001). The glomerular infiltrations of LFA1alpha+ and CR4+ cells were highly correlated with each other (r = 0.884, P < 0.00001), and both cell types were significantly correlated with urine protein (respectively, r = 0.426 and 0.478, P < 0.001 and 0.0001). When the change in these parameters between the time of the initial and follow-up biopsies was evaluated, there was a significant correlation between the change in glomerular expression of ICAM1 (DeltaICAM1) and MCP (DeltaMCP) as well as between the change in glomerular infiltration of LFA1alpha+ cells (DeltaLFA1alpha+) and CR4+ cells (DeltaCR4+). Both DeltaLFA1alpha+ and DeltaCR4+ were significantly correlated with the change in urine protein. These findings suggest that ICAM1/LFA1 interaction and MCP-mediated C3bi/C3biR interaction cooperate and participate in persistent glomerular infiltration of immune cells in immunoglobulin A nephropathy, and that these LFA1alpha+ and C3biR+ cells contribute to the induction of proteinuria.
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Affiliation(s)
- T Ootaka
- Second Department of Internal Medicine, Tohoku University School of Medicine, Sendai, Japan
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47
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48
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Quigg RJ, Morgan BP, Holers VM, Adler S, Sneed AE, Lo CF. Complement regulation in the rat glomerulus: Crry and CD59 regulate complement in glomerular mesangial and endothelial cells. Kidney Int 1995; 48:412-21. [PMID: 7564108 DOI: 10.1038/ki.1995.309] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The complement regulators, decay accelerating factor, membrane cofactor protein, and CD59 are present in human glomeruli. Crry is the rodent analogue to the former two proteins. In this study, we examined complement regulation in cultured rat glomerular endothelial cells (GEnC) and mesangial cells (MES). Immunoprecipitation of 125I-labeled membrane proteins and Western blotting studies were performed with anti-Crry and anti-CD59. In both GEnC and MES, Crry was present as 53, 65, and 78 kD proteins. The 20 kD CD59 was apparent in GEnC. CD59 was also present in MES, but in relatively smaller quantities. By Northern analyses, 1.8 kb CD59 mRNA was present in GEnC as well as in RNA from isolated rat glomeruli. mRNA for Crry was present in both GEnC and MES as 2.2 kb species. The functional significance of these proteins was evaluated next. Anti-Thy 1.1 IgG was used to activate the complement classical pathway in MES. To inhibit the function of the complement regulators, anti-CD59 and/or anti-Crry F(ab')2 antibodies were added with anti-Thy 1.1. Inhibition of Crry function led to enhanced cytotoxicity, while there was no effect when CD59 function was inhibited. The complement alternative pathway was studied by adding complement in Mg-EGTA buffer. Inhibition of Crry led to productive alternative pathway activation, which was accentuated by anti-CD59 when Crry was incompletely inhibited. Alternative pathway regulation was also evaluated in GEnC. Inhibition of CD59 function alone had no effect in GEnC, while inhibition of Crry led to significant cytotoxicity from alternative pathway activation. Under conditions in which Crry was inactive, inhibition of CD59 further enhanced cytotoxicity. Therefore, Crry is present in both GEnC and MES and restricts the complement alternative pathway in both cell types. Crry also regulates the classical pathway in MES. CD59 is present and functionally active in GEnC, while it appears to have a minor role in MES.
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Affiliation(s)
- R J Quigg
- Department of Medicine, University of Chicago, Illinois, USA
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Cosio FG, Shibata T, Rovin BH, Birmingham DJ. Effects of complement activation products on the synthesis of decay accelerating factor and membrane cofactor protein by human mesangial cells. Kidney Int 1994; 46:986-92. [PMID: 7532249 DOI: 10.1038/ki.1994.358] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
We previously demonstrated that activation of terminal complement components (C8 and/or C9) increases the synthesis and expression of decay accelerating factor (DAF) on human glomerular cells. DAF is a cell membrane-associated complement regulatory protein that inhibits complement activation on cell surfaces. In the present studies we evaluated, first, the mechanisms by which complement activation stimulates DAF synthesis, and second the effect of complement activation on the synthesis. and expression of membrane cofactor protein (MCP), another complement regulatory protein, by human mesangial cells (HMC) in culture. Complement activation by immune complexes resulted in increased DAF mRNA levels by at least two mechanisms: deposition of activated C3 on HMC and generation of soluble complement activation products, specifically C5a. The increase in DAF mRNA levels induced by activated C3 or C5a was short lived (less than 4 hr). In contrast, the up-regulation of DAF mRNA levels induced by activation of the complete complement cascade persisted for at least eight hours. The effect of complement activation on DAF mRNA levels was not affected by cycloheximide, a protein synthesis inhibitor. However, cycloheximide alone resulted in a significant up-regulation of DAF mRNA levels on HMC. In contrast to those findings complement activation did not cause an up-regulation of MCP mRNA, nor an increase in the synthesis of this protein. However, by FACS, complement produced a small but significant increase of MCP protein levels on HMC. In conclusion, both MCP and DAF are present on HMC. Several activated complement components are capable of increasing DAF mRNA levels, but DAF protein levels increase only after activation of the whole complement cascade.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- F G Cosio
- Department of Internal Medicine, Nephrology, Ohio State University, Columbus
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50
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Ichida S, Yuzawa Y, Okada H, Yoshioka K, Matsuo S. Localization of the complement regulatory proteins in the normal human kidney. Kidney Int 1994; 46:89-96. [PMID: 7523758 DOI: 10.1038/ki.1994.247] [Citation(s) in RCA: 111] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The kidney is an organ where complement-mediated tissue injuries take place by various stimuli. To assess how the kidney is protected from the autologous complement attack, comparative localization of decay accelerating factor (DAF), membrane cofactor protein (MCP) and 20 kDa homologous restriction factor (HRF20) was studied in the normal human kidney. Specific monoclonal antibodies to DAF, MCP and HRF20 were used for the study. Studies by immunofluorescence and immunoelectron microscopy showed that the distribution of each protein in the kidney was complementary to each other in most parts. MCP and HRF20 were clearly seen in the glomerular capillaries, while DAF was only faintly observed. Juxtaglomerular apparatus was abundant in DAF and MCP but not in HRF20. HRF20 was most strongly expressed in the peritubular capillaries where MCP was not detectable. Basolateral membranes of the proximal tubules and collecting ducts expressed MCP strongly, while there was no expression of DAF in the proximal tubules. Interestingly, both DAF and MCP, which inhibit complement activation at C3/C4 level, were not expressed in the apical portion of the tubular cells including proximal tubule brush border. In contrast, HRF20 was expressed on the apical part of the tubules. Medullary interstitium strongly expressed MCP but not DAF. Based on these observations, we conclude that each segment of the kidney is protected from the complement attack by the different combination of complement regulatory proteins. We speculate that the tubular cells might be fragile when complements are activated inside the tubular lumen, because there is no expression of complement regulatory proteins which inhibit C3 convertase.
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Affiliation(s)
- S Ichida
- Third Department of Internal Medicine, Nagoya University School of Medicine, Japan
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