1
|
Holers VM, Frank RM, Zuscik M, Keeter C, Scheinman RI, Striebich C, Simberg D, Clay MR, Moreland LW, Banda NK. Decay-Accelerating Factor Differentially Associates With Complement-Mediated Damage in Synovium After Meniscus Tear as Compared to Anterior Cruciate Ligament Injury. Immune Netw 2024; 24:e17. [PMID: 38725672 PMCID: PMC11076301 DOI: 10.4110/in.2024.24.e17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 04/01/2024] [Accepted: 04/08/2024] [Indexed: 05/12/2024] Open
Abstract
We have reported that anterior cruciate ligament (ACL) injury leads to the differential dysregulation of the complement system in the synovium as compared to meniscus tear (MT) and proposed this as a mechanism for a greater post-injury prevalence of post traumatic osteoarthritis (PTOA). To explore additional roles of complement proteins and regulators, we determined the presence of decay-accelerating factor (DAF), C5b, and membrane attack complexes (MACs, C5b-9) in discarded surgical synovial tissue (DSST) collected during arthroscopic ACL reconstructive surgery, MT-related meniscectomy, osteoarthritis (OA)-related knee replacement surgery and normal controls. Multiplexed immunohistochemistry was used to detect and quantify complement proteins. To explore the involvement of body mass index (BMI), after these 2 injuries, we examined correlations among DAF, C5b, MAC and BMI. Using these approaches, we found that synovial cells after ACL injury expressed a significantly lower level of DAF as compared to MT (p<0.049). In contrast, C5b staining synovial cells were significantly higher after ACL injury (p<0.0009) and in OA DSST (p<0.039) compared to MT. Interestingly, there were significantly positive correlations between DAF & C5b (r=0.75, p<0.018) and DAF & C5b (r=0.64 p<0.022) after ACL injury and MT, respectively. The data support that DAF, which should normally dampen C5b deposition due to its regulatory activities on C3/C5 convertases, does not appear to exhibit that function in inflamed synovia following either ACL injury or MT. Ineffective DAF regulation may be an additional mechanism by which relatively uncontrolled complement activation damages tissue in these injury states.
Collapse
Affiliation(s)
- V. Michael Holers
- Division of Rheumatology, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Rachel M. Frank
- Department of Orthopedics and the Colorado Program for Musculoskeletal Research, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Michael Zuscik
- Department of Orthopedics and the Colorado Program for Musculoskeletal Research, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Carson Keeter
- Department of Orthopedics and the Colorado Program for Musculoskeletal Research, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Robert I. Scheinman
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Christopher Striebich
- Division of Rheumatology, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Dmitri Simberg
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Michael R. Clay
- Department of Pathology, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Larry W. Moreland
- Division of Rheumatology, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
- Department of Orthopedics and the Colorado Program for Musculoskeletal Research, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Nirmal K. Banda
- Division of Rheumatology, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
| |
Collapse
|
2
|
Mastellos DC, Hajishengallis G, Lambris JD. A guide to complement biology, pathology and therapeutic opportunity. Nat Rev Immunol 2024; 24:118-141. [PMID: 37670180 DOI: 10.1038/s41577-023-00926-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/20/2023] [Indexed: 09/07/2023]
Abstract
Complement has long been considered a key innate immune effector system that mediates host defence and tissue homeostasis. Yet, growing evidence has illuminated a broader involvement of complement in fundamental biological processes extending far beyond its traditional realm in innate immunity. Complement engages in intricate crosstalk with multiple pattern-recognition and signalling pathways both in the extracellular and intracellular space. Besides modulating host-pathogen interactions, this crosstalk guides early developmental processes and distinct cell trajectories, shaping tissue immunometabolic and regenerative programmes in different physiological systems. This Review provides a guide to the system-wide functions of complement. It highlights illustrative paradigm shifts that have reshaped our understanding of complement pathobiology, drawing examples from evolution, development of the central nervous system, tissue regeneration and cancer immunity. Despite its tight spatiotemporal regulation, complement activation can be derailed, fuelling inflammatory tissue pathology. The pervasive contribution of complement to disease pathophysiology has inspired a resurgence of complement therapeutics with major clinical developments, some of which have challenged long-held dogmas. We thus highlight major therapeutic concepts and milestones in clinical complement intervention.
Collapse
Affiliation(s)
| | - George Hajishengallis
- Department of Basic and Translational Sciences, Penn Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - John D Lambris
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| |
Collapse
|
3
|
Xie XX, Chen ZJ, Zhu QG, Yu Q, Lian TY, Xu XL, Chen Y, Song WH. Large-scale separation of alkaloids from Corydalis decumbens by pH-zone-refining centrifugal partition chromatography and their anticomplement activity. J Sep Sci 2024; 47:e2300577. [PMID: 38109069 DOI: 10.1002/jssc.202300577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 11/08/2023] [Accepted: 12/05/2023] [Indexed: 12/19/2023]
Abstract
Centrifugal partition chromatography in the pH-zone-refining mode was successfully applied to the separation of alkaloids from the crude extract of Corydalis decumbens. The experiment was performed with a two-phase solvent system composed of petroleum ether-ethyl acetate-ethanol-water (5:5:3:7, v/v/v/v) where triethylamine (10 mM) was added to the stationary phase and hydrochloric acid (10 mM) to the mobile phase. From 1.6 g of the crude extract, 43 mg protopine, 189 mg (+)-egenine, and 158 mg tetrahydropalmatine were obtained with a purity of 98.2%, 94.6%, and 96.7%, respectively. Tetrahydropalmatine showed an interesting anticomplement effect with CH50 0.11 and AP50 0.25 mg/mL, respectively. In a mechanistic study, tetrahydropalmatine interacted with C1, C3, C4, and C5 components in the complement activation cascade.
Collapse
Affiliation(s)
- Xin-Xin Xie
- Department of Pharmacy, Shanghai Skin Disease Hospital, School of Medicine, Tongji University, Shanghai, P. R. China
- Shanghai Engineering Research Center of External Chinese Medicine, Shanghai, P. R. China
| | - Zhong-Jian Chen
- Department of Pharmacy, Shanghai Skin Disease Hospital, School of Medicine, Tongji University, Shanghai, P. R. China
- Shanghai Engineering Research Center of External Chinese Medicine, Shanghai, P. R. China
| | - Quan-Gang Zhu
- Department of Pharmacy, Shanghai Skin Disease Hospital, School of Medicine, Tongji University, Shanghai, P. R. China
- Shanghai Engineering Research Center of External Chinese Medicine, Shanghai, P. R. China
| | - Qin Yu
- Department of Pharmacy, Shanghai Skin Disease Hospital, School of Medicine, Tongji University, Shanghai, P. R. China
- Shanghai Engineering Research Center of External Chinese Medicine, Shanghai, P. R. China
| | - Tian-Yan Lian
- Department of Pharmacy, Shanghai Skin Disease Hospital, School of Medicine, Tongji University, Shanghai, P. R. China
- Shanghai Engineering Research Center of External Chinese Medicine, Shanghai, P. R. China
| | - Xue-Lian Xu
- Department of Pharmacy, Shanghai Skin Disease Hospital, School of Medicine, Tongji University, Shanghai, P. R. China
- Shanghai Engineering Research Center of External Chinese Medicine, Shanghai, P. R. China
| | - Ya Chen
- Department of Pharmacy, Shanghai Skin Disease Hospital, School of Medicine, Tongji University, Shanghai, P. R. China
- Shanghai Engineering Research Center of External Chinese Medicine, Shanghai, P. R. China
| | - Wei-Hua Song
- Department of Clinical Pharmacy, Shanghai General Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, P. R. China
| |
Collapse
|
4
|
Zhou L, Chai JH, Zhang Y, Jing XJ, Kong XW, Liang J, Xia YG. TMT-Based Proteomics Reveal the Mechanism of Action of Amygdalin against Rheumatoid Arthritis in a Rat Model through Regulation of Complement and Coagulation Cascades. Molecules 2023; 28:7126. [PMID: 37894605 PMCID: PMC10609517 DOI: 10.3390/molecules28207126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 10/13/2023] [Accepted: 10/13/2023] [Indexed: 10/29/2023] Open
Abstract
The limitations of current medications for treating rheumatoid arthritis (RA) emphasize the urgent need for the development of new drugs. This study aimed to investigate the potential anti-RA mechanism of amygdalin using tandem mass tag (TMT)-based quantitative proteomics technology. First, the anti-RA activity of amygdalin was evaluated in a Complete Freund's adjuvant (CFA)-induced rat model. Then, the roles and importance of proteins in the extracted rat joint tissue were evaluated using TMT-based quantitative proteomics technology. A bioinformatics analysis was used to analyze differentially abundant proteins (DAPs). A proteomics analysis identified 297 DAPs in the amygdalin group compared with the model group, of which 53 upregulated proteins and 51 downregulated proteins showed opposite regulatory trends to the DAPs produced after modeling. According to enrichment analyses of the DAPs, the signaling pathways with a high correlation degree were determined to be the complement and coagulation cascades. Furthermore, western blotting and molecular docking were used to further validate the key node proteins, e.g., complement C1s subcomponent (C1s), component C3 (C3) and kininogen 1 (Kng1). These results suggest that amygdalin may be a promising agent for treating RA by regulating the complement and coagulation cascades.
Collapse
Affiliation(s)
| | | | | | | | | | - Jun Liang
- Key Laboratory of Basic and Application Research of Beiyao, Heilongjiang University of Chinese Medicine, Ministry of Education, 24 Heping Road, Harbin 150040, China
| | - Yong-Gang Xia
- Key Laboratory of Basic and Application Research of Beiyao, Heilongjiang University of Chinese Medicine, Ministry of Education, 24 Heping Road, Harbin 150040, China
| |
Collapse
|
5
|
Holers VM. Complement therapeutics are coming of age in rheumatology. Nat Rev Rheumatol 2023; 19:470-485. [PMID: 37337038 DOI: 10.1038/s41584-023-00981-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/10/2023] [Indexed: 06/21/2023]
Abstract
The complement system was described over 100 years ago, and it is well established that activation of this pathway accompanies the great majority of autoimmune and inflammatory diseases. In addition, over three decades of work in murine models of human disease have nearly universally demonstrated that complement activation is upstream of tissue injury and the engagement of pro-inflammatory mechanisms such as the elaboration of cytokines and chemokines, as well as myeloid cell recruitment and activation. With that background, and taking advantage of advances in the development of biologic and small-molecule therapeutics, the creation and clinical evaluation of complement therapeutics is now rapidly expanding. This article reviews the current state of the complement therapeutics field, with a focus on their use in diseases cared for or consulted upon by rheumatologists. Included is an overview of the activation mechanisms and components of the system, in addition to the mechanisms by which the complement system interacts with other immune system constituents. The various therapeutic approaches to modulating the system in rheumatic and autoimmune diseases are reviewed. To understand how best to clinically assess the complement system, methods of its evaluation are described. Finally, next-generation therapeutic and diagnostic advances that can be envisioned for the future are discussed.
Collapse
Affiliation(s)
- V Michael Holers
- Medicine/Rheumatology, University of Colorado School of Medicine, Aurora, CO, USA.
| |
Collapse
|
6
|
Triggianese P, Conigliaro P, De Martino E, Monosi B, Chimenti MS. Overview on the Link Between the Complement System and Auto-Immune Articular and Pulmonary Disease. Open Access Rheumatol 2023; 15:65-79. [PMID: 37214353 PMCID: PMC10198272 DOI: 10.2147/oarrr.s318826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Accepted: 05/05/2023] [Indexed: 05/24/2023] Open
Abstract
Complement system (CS) dysregulation is a key factor in the pathogenesis of different autoimmune diseases playing a central role in many immune innate and adaptive processes. Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by ta breach of self-tolerance leading to a synovitis and extra-articular manifestations. The CS is activated in RA and seems not only to mediate direct tissue damage but also play a role in the initiation of RA pathogenetic mechanisms through interactions with citrullinated proteins. Interstitial lung disease (ILD) represents the most common extra-articular manifestation that can lead to progressive fibrosis. In this review, we focused on the evidence of CS dysregulation in RA and in ILD, and highlighted the role of the CS in both the innate and adaptive immune responses in the development of diseases, by using idiopathic pulmonary fibrosis as a model of lung disease. As a proof of concept, we dissected the evidence that several treatments used to treat RA and ILD such as glucocorticoids, pirfenidone, disease modifying antirheumatic drugs, targeted biologics such as tumor necrosis factor (TNF)-inhibitors, rituximab, tocilizumab, and nintedanib may act indirectly on the CS, suggesting that the CS might represent a potential therapeutic target in these complex diseases.
Collapse
Affiliation(s)
- Paola Triggianese
- Department of Systems Medicine, Rheumatology, Allergology and Clinical Immunology, University of Rome Tor Vergata, Rome, Italy
| | - Paola Conigliaro
- Department of Systems Medicine, Rheumatology, Allergology and Clinical Immunology, University of Rome Tor Vergata, Rome, Italy
| | - Erica De Martino
- Department of Systems Medicine, Rheumatology, Allergology and Clinical Immunology, University of Rome Tor Vergata, Rome, Italy
| | - Benedetta Monosi
- Department of Systems Medicine, Rheumatology, Allergology and Clinical Immunology, University of Rome Tor Vergata, Rome, Italy
| | - Maria Sole Chimenti
- Department of Systems Medicine, Rheumatology, Allergology and Clinical Immunology, University of Rome Tor Vergata, Rome, Italy
| |
Collapse
|
7
|
Holers VM, Frank RM, Clauw A, Seifert J, Zuscik M, Asokan S, Striebich C, Clay MR, Moreland LW, Banda NK. Potential causal role of synovial complement system activation in the development of post-traumatic osteoarthritis after anterior cruciate ligament injury or meniscus tear. Front Immunol 2023; 14:1146563. [PMID: 37207197 PMCID: PMC10189880 DOI: 10.3389/fimmu.2023.1146563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 03/24/2023] [Indexed: 05/21/2023] Open
Abstract
Anterior cruciate ligament (ACL) injury and meniscal tear (MT) are major causal factors for developing post-traumatic osteoarthritis (PTOA), but the biological mechanism(s) are uncertain. After these structural damages, the synovium could be affected by complement activation that normally occurs in response to tissue injury. We explored the presence of complement proteins, activation products, and immune cells, in discarded surgical synovial tissue (DSST) collected during arthroscopic ACL reconstructive surgery, MT-related meniscectomy and from patients with OA. Multiplexed immunohistochemistry (MIHC) was used to determine the presence of complement proteins, receptors and immune cells from ACL, MT, OA synovial tissue vs. uninjured controls. Examination of synovium from uninjured control tissues did not reveal the presence of complement or immune cells. However, DSST from patients undergoing ACL and MT repair demonstrated increases in both features. In ACL DSST, a significantly higher percentage of C4d+, CFH+, CFHR4+ and C5b-9+ synovial cells were present compared with MT DSST, but no major differences were seen between ACL and OA DSST. Increased cells expressing C3aR1 and C5aR1, and a significant increase in mast cells and macrophages, were found in ACL as compared to MT synovium. Conversely, the percentage of monocytes was increased in the MT synovium. Our data demonstrate that complement is activated in the synovium and is associated with immune cell infiltration, with a more pronounced effect following ACL as compared to MT injury. Complement activation, associated with an increase in mast cells and macrophages after ACL injury and/or MT, may contribute to the development of PTOA.
Collapse
Affiliation(s)
- V. Michael Holers
- Division of Rheumatology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Rachel M. Frank
- Department of Orthopedics and the Colorado Program for Musculoskeletal Research, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Andrew Clauw
- Department of Orthopedics and the Colorado Program for Musculoskeletal Research, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Jennifer Seifert
- Department of Orthopedics and the Colorado Program for Musculoskeletal Research, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Michael Zuscik
- Department of Orthopedics and the Colorado Program for Musculoskeletal Research, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Sakthi Asokan
- Division of Rheumatology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Christopher Striebich
- Division of Rheumatology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Michael R. Clay
- Department of Pathology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Larry W. Moreland
- Division of Rheumatology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Department of Orthopedics and the Colorado Program for Musculoskeletal Research, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Nirmal K. Banda
- Division of Rheumatology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| |
Collapse
|
8
|
Coss SL, Zhou D, Chua GT, Aziz RA, Hoffman RP, Wu YL, Ardoin SP, Atkinson JP, Yu CY. The complement system and human autoimmune diseases. J Autoimmun 2023; 137:102979. [PMID: 36535812 PMCID: PMC10276174 DOI: 10.1016/j.jaut.2022.102979] [Citation(s) in RCA: 30] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 12/11/2022] [Indexed: 12/23/2022]
Abstract
Genetic deficiencies of early components of the classical complement activation pathway (especially C1q, r, s, and C4) are the strongest monogenic causal factors for the prototypic autoimmune disease systemic lupus erythematosus (SLE), but their prevalence is extremely rare. In contrast, isotype genetic deficiency of C4A and acquired deficiency of C1q by autoantibodies are frequent among patients with SLE. Here we review the genetic basis of complement deficiencies in autoimmune disease, discuss the complex genetic diversity seen in complement C4 and its association with autoimmune disease, provide guidance as to when clinicians should suspect and test for complement deficiencies, and outline the current understanding of the mechanisms relating complement deficiencies to autoimmunity. We focus primarily on SLE, as the role of complement in SLE is well-established, but will also discuss other informative diseases such as inflammatory arthritis and myositis.
Collapse
Affiliation(s)
- Samantha L Coss
- Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, OH, USA; Department of Pediatrics, The Ohio State University, Columbus, OH, USA.
| | - Danlei Zhou
- Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, OH, USA; Department of Pediatrics, The Ohio State University, Columbus, OH, USA
| | - Gilbert T Chua
- Department of Pediatrics and Adolescent Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Rabheh Abdul Aziz
- Department of Pediatrics, The Ohio State University, Columbus, OH, USA; Department of Allergy, Immunology and Rheumatology, University of Buffalo, NY, USA
| | - Robert P Hoffman
- Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, OH, USA; Department of Pediatrics, The Ohio State University, Columbus, OH, USA
| | - Yee Ling Wu
- Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, OH, USA; Department of Pediatrics, The Ohio State University, Columbus, OH, USA; Department of Microbiology and Immunology, Loyola University Chicago, Maywood, IL, USA
| | - Stacy P Ardoin
- Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, OH, USA; Department of Pediatrics, The Ohio State University, Columbus, OH, USA
| | - John P Atkinson
- Department of Medicine, Division of Rheumatology, Washington University School of Medicine, St Louis, MO, USA
| | - Chack-Yung Yu
- Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, OH, USA; Department of Pediatrics, The Ohio State University, Columbus, OH, USA.
| |
Collapse
|
9
|
West EE, Kemper C. Complosome - the intracellular complement system. Nat Rev Nephrol 2023:10.1038/s41581-023-00704-1. [PMID: 37055581 PMCID: PMC10100629 DOI: 10.1038/s41581-023-00704-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/10/2023] [Indexed: 04/15/2023]
Abstract
The complement system is a recognized pillar of host defence against infection and noxious self-derived antigens. Complement is traditionally known as a serum-effective system, whereby the liver expresses and secretes most complement components, which participate in the detection of bloodborne pathogens and drive an inflammatory reaction to safely remove the microbial or antigenic threat. However, perturbations in normal complement function can cause severe disease and, for reasons that are currently not fully understood, the kidney is particularly vulnerable to dysregulated complement activity. Novel insights into complement biology have identified cell-autonomous and intracellularly active complement - the complosome - as an unexpected central orchestrator of normal cell physiology. For example, the complosome controls mitochondrial activity, glycolysis, oxidative phosphorylation, cell survival and gene regulation in innate and adaptive immune cells, and in non-immune cells, such as fibroblasts and endothelial and epithelial cells. These unanticipated complosome contributions to basic cell physiological pathways make it a novel and central player in the control of cell homeostasis and effector responses. This discovery, together with the realization that an increasing number of human diseases involve complement perturbations, has renewed interest in the complement system and its therapeutic targeting. Here, we summarize the current knowledge about the complosome across healthy cells and tissues, highlight contributions from dysregulated complosome activities to human disease and discuss potential therapeutic implications.
Collapse
Affiliation(s)
- Erin E West
- National Heart, Lung, and Blood Institute (NHLBI), National Institutes of Health (NIH), Complement and Inflammation Research Section (CIRS), Bethesda, MD, USA
| | - Claudia Kemper
- National Heart, Lung, and Blood Institute (NHLBI), National Institutes of Health (NIH), Complement and Inflammation Research Section (CIRS), Bethesda, MD, USA.
| |
Collapse
|
10
|
Holers VM. Contributions of animal models to mechanistic understandings of antibody-dependent disease and roles of the amplification loop. Immunol Rev 2023; 313:181-193. [PMID: 36111456 DOI: 10.1111/imr.13136] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The complement system plays an important pathophysiologic role in human diseases associated with immune or ischemic insults. In addition to understanding the effector mechanisms that are important for the biological effects of the system, substantial efforts have gone into understanding which specific complement activation pathways generate these potent effects. These approaches include the use of gene-targeted mice and specific pathway inhibitors, as well as the integration of human disease genetic and biomarker studies. In some disease states, it is quite clear that the alternate pathway plays a unique role in the initiation of the complement system. However, although initially a widely unexpected finding, it has now been shown in many tissue-based disease models and in initial human studies that engagement of the amplification loop is also essential for tissue injury when the classical and/or lectin pathways initiate pathway activation through pathogenic autoantibodies. This review provides evidence for such a conclusion through animal models, focusing on pathogenic antibody passive transfer models but also other relevant experimental systems. These data, along with initial biomarkers and clinical trial outcomes in human diseases that are associated with pathogenic autoantibodies, suggest that targeting the alternative pathway amplification loop may have near-universal therapeutic utility for tissue-based diseases.
Collapse
Affiliation(s)
- V Michael Holers
- Division of Rheumatology, University of Colorado School of Medicine, Aurora, Colorado, USA
| |
Collapse
|