Topological Localization of Monomeric C-reactive Protein Determines Proinflammatory Endothelial Cell Responses

Li, Haiyun; Wang, Jing; Wu, Yuexin; Zhang, Lin; Liu, Zu-Pei; Filep, János G.; Potempa, Lawrence A.; Wu, Yi; Ji, Shang‐Rong

doi:10.1074/jbc.m114.555318

Cited by 43 publications

(35 citation statements)

References 37 publications

(30 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Rather than reflecting a conflict with previous data, we hypothesize that the involvement of both isoforms represents different time points in the proinflammatory cascade (Fig. 8)432. The data presented here confirm previous studies that the proinflammatory properties of CRP are regulated by conformational changes413.…”

Section: Discussionsupporting

confidence: 73%

See 1 more Smart Citation

Transitional changes in the CRP structure lead to the exposure of proinflammatory binding sites

et al. 2017

Self Cite

View full text Add to dashboard Cite

C-reactive protein (CRP) concentrations rise in response to tissue injury or infection. Circulating pentameric CRP (pCRP) localizes to damaged tissue where it leads to complement activation and further tissue damage. In-depth knowledge of the pCRP activation mechanism is essential to develop therapeutic strategies to minimize tissue injury. Here we demonstrate that pCRP by binding to cell-derived microvesicles undergoes a structural change without disrupting the pentameric symmetry (pCRP*). pCRP* constitutes the major CRP species in human-inflamed tissue and allows binding of complement factor 1q (C1q) and activation of the classical complement pathway. pCRP*–microvesicle complexes lead to enhanced recruitment of leukocytes to inflamed tissue. A small-molecule inhibitor of pCRP (1,6-bis(phosphocholine)-hexane), which blocks the pCRP–microvesicle interactions, abrogates these proinflammatory effects. Reducing inflammation-mediated tissue injury by therapeutic inhibition might improve the outcome of myocardial infarction, stroke and other inflammatory conditions.

show abstract

Section: Discussionsupporting

confidence: 73%

“…The difference in the CD spectrum indicates that the mCRP protein is significantly more disordered than pCRP. This partially unfolded state might account for the rapid clearance of mCRP from circulation3233. We examined whether mCRP and pCRP* influence uptake of CMFDA-labelled microvesicles in human macrophages.…”

Section: Resultsmentioning

confidence: 99%

Transitional changes in the CRP structure lead to the exposure of proinflammatory binding sites

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

“…mCRP can then induce pro-inflammatory effects on cells such as monocytes and endothelial cells, including the production of more MPs. More specifically, mCRP has been shown to bind predominantly to the apical surface of endothelial cells that are enriched in lipid raft domains, promoting the release of proinflammatory cytokines, the generation of reactive oxygen species, and adhesion molecule expression [34,35]. …”

Section: Discussionmentioning

confidence: 99%

Plasma Levels of Endothelial Microparticles Bearing Monomeric C-reactive Protein are Increased in Peripheral Artery Disease

Crawford

Trial

Nambi

et al. 2016

J. of Cardiovasc. Trans. Res.

View full text Add to dashboard Cite

C-reactive Protein (CRP) as an indicator of cardiovascular disease (CVD) has shown limited sensitivity. We demonstrate that two isoforms of CRP (pentameric, pCRP and monomeric, mCRP) present in soluble form or on microparticles (MPs) have different biological effects and are not all measured by clinical CRP assays. The hsCRP assay did not measure pCRP or mCRP on MPs, whereas flow cytometry did. MPs derived from endothelial cells, particularly those bearing mCRP, were elevated in PAD patients compared to controls. The numbers of mCRP+ endothelial MPs did not correlate with hsCRP measurements of soluble pCRP, indicating their independent modulation. In controls, statins lowered mCRP+ endothelial MPs. In a model of vascular inflammation, mCRP induced endothelial shedding of MPs and was proinflammatory, while pCRP was anti-inflammatory. mCRP on endothelial MPs may be both an unmeasured indicator of, and an amplifier of, vascular disease, and its detection might improve risk sensitivity.

show abstract

“…Monocyte Adhesion to Endothelial Cells-Primary human aortic endothelial cells (HAEC, Lifeline Cell Technology, Frederick, MD; catalogue number: FC-0027; lot number: 01381) were cultured as described (19,29). Confluent HAEC monolayers (passages 3-6) in 24-well plates or on coverslips were rinsed twice with PBS containing 1 mM CaCl 2 and 1 mM MgCl 2 and labeled with Calcein AM for 15 min at 37°C.…”

Section: Methodsmentioning

confidence: 99%

“…mCRP is a potent activator of endothelial cells (ECs) through interaction with cholesterol-enriched lipid rafts when applied apically (29,44) and EC activation is an early event in atherosclerosis, leading to the adhesion and entry of monocytes into vessel walls (45). Apical stimulation of HAEC monolayers with mCRP strongly up-regulated surface expression of adhesion molecules (Fig.…”

Section: Cbs Inhibits Proinflammatory Actions Of Mcrp In Vitro and Inmentioning

confidence: 99%

An Intrinsically Disordered Motif Mediates Diverse Actions of Monomeric C-reactive Protein

Wang

Meng

et al. 2016

Journal of Biological Chemistry

Self Cite

View full text Add to dashboard Cite

C-reactive protein (CRP) 3 is a major human acute phase reactant composed of five identical subunits (1, 2). Accumulating evidence demonstrates that the actions of CRP depend on conformation and localization (3-5). CRP is primarily produced by the liver and circulates in the blood as a pentamer but is induced to dissociate into subunits (monomeric CRP, mCRP) upon interaction with the microenvironment at inflammatory loci (6 -18). mCRP exhibits markedly enhanced activities and recognizes an expanded list of binding partners. Following reduction of the intra-subunit disulfide bond, mCRP can be further activated (19). The degradation of mCRP, on the other hand, would generate bioactive fragments showing anti-inflammatory actions (20 -23). The differential contributions of these CRP conformations at distinct locations may therefore account for the intense controversies regarding the function of CRP in animal models and in clinical studies (3-5). mCRP appears to be the major conformation of CRP that regulates local inflammation (3-5), yet how it acts remains incompletely understood. In particular, though the markedly enhanced binding capability of mCRP underlies its actions, little is known through which sites mCRP recognizes diverse ligands. Consequently, no means is available to specifically modulate the actions of mCRP, which is necessary for clarifying the exact contributions of different CRP conformations in vitro and in vivo. The current study was designed to identify the recognition site of mCRP for ligand binding. The results unexpectedly demonstrated cholesterol binding sequence (CBS) as a versatile motif that mediates the interactions of mCRP with different types of ligands, including two newly identified herein. We further showed that synthetic CBS peptide was able to inhibit the proinflammatory actions of mCRP both in vitro and in vivo. Hence, optimized CBS peptide may be developed as a potential inhibitor of mCRP. Experimental ProceduresReagents-Human native CRP (purity Ͼ 99%) purified from ascites was purchased from the BindingSite (Birmingham, UK; catalogue number: BP300.X). mCRP and acylated Cys-mutated mCRP was prepared as described (19,24). Proteins were dialyzed to remove NaN 3 , and passed through Detoxi-Gel Columns (Thermo Fisher Scientific, Rockford, IL; catalogue number: 20344) to remove endotoxin when necessary. CRP peptides (purity Ͼ 98%) were synthesized by Science Peptide Biological Technology (Shanghai, China). Lyophilized peptides were reconstituted aseptically with DMSO at 40 mg/ml and stored at Ϫ20°C in aliquots or kept at 4°C for a maximum of 1 week.

show abstract

Topological Localization of Monomeric C-reactive Protein Determines Proinflammatory Endothelial Cell Responses

Cited by 43 publications

References 37 publications

Transitional changes in the CRP structure lead to the exposure of proinflammatory binding sites

Transitional changes in the CRP structure lead to the exposure of proinflammatory binding sites

Plasma Levels of Endothelial Microparticles Bearing Monomeric C-reactive Protein are Increased in Peripheral Artery Disease

An Intrinsically Disordered Motif Mediates Diverse Actions of Monomeric C-reactive Protein

Contact Info

Product

Resources

About