scholarly journals Extracellular vesicles are associated with C-reactive protein in sepsis

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Birgit Fendl ◽  
René Weiss ◽  
Tanja Eichhorn ◽  
Ingrid Linsberger ◽  
Taras Afonyushkin ◽  
...  

AbstractThere is increasing evidence that C-reactive protein (CRP) can mediate inflammatory reactions following the transformation of functionally inert pentameric CRP (pCRP) into its structural isoform pCRP* and into monomeric CRP (mCRP). This conversion can occur on the membranes of apoptotic or activated cells or on extracellular vesicles (EVs) shed from the cell surface. Here, we characterized the association of CRP with EVs in plasma from sepsis patients using flow cytometry, and found highly elevated levels of total EV counts and CRP+ EVs as compared to healthy individuals. We further assessed the ability of PentraSorb CRP, an extracorporeal device for the adsorption of CRP, to deplete free CRP and CRP+ EVs. Treatment of septic plasma with the adsorbent in vitro resulted in almost complete removal of both, free CRP and CRP+ EVs, while total EV counts remained largely unaffected, indicating the detachment of CRP from the EV surface. EVs from septic plasma elicited a release of interleukin-8 from cultured human monocytes, which was significantly reduced by adsorbent treatment prior to EV isolation. Our findings provide evidence that CRP+ EVs exhibit pro-inflammatory characteristics and can contribute to the spreading of inflammation throughout the circulation on top of their pro-coagulant activity.

1975 ◽  
Vol 142 (5) ◽  
pp. 1065-1077 ◽  
Author(s):  
A.P. Osmand ◽  
R.F. Mortensen ◽  
Joan Siegel ◽  
H. Gewurz

Interactions of CRP with various substrates in the presence of human serum have been shown to result in efficient activation of C components C1-C5. We now report the ability of CRP to initiate C-dependent hemolysis. For this purpose CRP was isolated by affinity chromatography using pneumococcal CPS and gel filtration; its purity was established by several criteria. Erythrocytes were coated with CPS (E-CPS) and passively sensitized with CRP. C-dependent lysis of these cells was observed upon the addition of suitably absorbed human serum, and the efficiency of hemolysis compared favorably with that initiated by rabbit IgG anti-CPS antibody. CRP also sensitized E-CPS for lysis by guinea pig C; partial lysis was seen when C4-deficient guinea pig serum was used, suggesting that CRP also shares with antibody the ability of CRP to fully activate the C system and provide further evidence for a role for CRP similar to that of antibody in the initiation and modulation of inflammatory reactions via the complete system.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Andreea Lorena Mateescu ◽  
Nicolae-Bogdan Mincu ◽  
Silvana Vasilca ◽  
Roxana Apetrei ◽  
Diana Stan ◽  
...  

AbstractThe purpose of the present study was to evaluate de influence of protein–sugar complexation on the stability and functionality of C-reactive protein, after exposure to constant high temperatures, in order to develop highly stable positive controls for in-vitro diagnostic tests. C-reactive protein is a plasmatic protein used as a biomarker for the diagnosis of a series of health problems such as ulcerative colitis, cardiovascular diseases, metabolic syndrome, due to its essential role in the evolution of chronic inflammation. The sugar–protein interaction was investigated using steady state and time resolved fluorescence. The results revealed that there are more than two classes of tryptophan, with different degree of accessibility for the quencher molecule. Our study also revealed that sugar–protein complexes have superior thermostability, especially after gamma irradiation at 2 kGy, the protein being stable and functional even after 22 days exposure to 40 °C.


2021 ◽  
Vol 13 ◽  
pp. 1759720X2110069
Author(s):  
Yanpan Gao ◽  
Yanyu Chen ◽  
Lun Wang ◽  
Chen Li ◽  
Wei Ge

Objective: Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome is a rare chronic inflammatory disorder and the underlying pathogenesis is unclear. In this study, 88 SAPHO patients and 118 healthy controls were recruited to investigate the role of serum-derived extracellular vesicles (SEVs) in SAPHO syndrome. Methods: Quantitative proteomics was applied for SEVs proteome identification, and ELISA and Western blotting was performed to verify the results of mass spectrum data. In vitro osteoclastogenesis and osteogenesis assay was used to confirm the effects of SEVs on bone metabolism. Results: Tandem mass tagging-based quantitative proteomic analysis of SAPHO SEVs revealed differential expressed proteins involved in bone metabolism. Of these, serum amyloid A-1 (SAA1) and C-reactive protein (CRP) were upregulated. Higher SAA1 levels in SAPHO patients were confirmed by ELISA. In addition, SAA1 levels were positively correlated with CRP, an inflammatory marker related to the condition of patients. In vitro celluler studies confirmed that SAPHO SEVs inhibited osteoclastogenesis in patients mainly in the active phase of the disease. Further analysis demonstrated that Nucleolin was upregulated in osteoclasts of active-phase patients under SAPHO SEVs stimulation. Conclusion: In this study, we identified SAA1 as an additional inflammation marker that can potentially assist the diagnosis of SAPHO syndrome, and speculated that Nucleolin is a key regulator of osteoclastogenesis in active-phase patients.


Blood ◽  
1996 ◽  
Vol 87 (5) ◽  
pp. 1862-1872 ◽  
Author(s):  
M Introna ◽  
VV Alles ◽  
M Castellano ◽  
G Picardi ◽  
L De Gioia ◽  
...  

Abstract Pentraxins, which include C reactive protein (CRP) and serum amyloid P component (SAP), are prototypic acute phase reactants that serve as indicators of inflammatory reactions. Here we report genomic and cDNA cloning of mouse ptx3 (mptx3), a member of the pentraxin gene family and characterize its extrahepatic expression in vitro and in vivo. mptx3 is organized into three exons on chromosome 3: the first (43 aa) and second exon (175 aa) code for the signal peptide and for a protein portion with no high similarity to known sequences the third (203 aa) for a domain related to classical pentraxins, which contains the “pentraxin family signature.” Analysis of the N terminal portion predicts a predominantly alpha helical structure, while the pentraxin domain of ptx3 is accommodated comfortably in the tertiary structure fold of SAP. Normal and transformed fibroblasts, undifferentiated and differentiated myoblasts, normal endothelial cells, and mononuclear phagocytes express mptx3 mRNA and release the protein in vitro on exposure to interleukin-1beta (IL-1beta) and tumor necrosis factor (TNF)alpha. mptx3 was induced by bacterial lipopolysaccharide in vivo in a variety of organs and, most strongly, in the vascular endothelium of skeletal muscle and heart. Thus, mptx3 shows a distinct pattern of in vivo expression indicative of a significant role in cardiovascular and inflammatory pathology.


1982 ◽  
Vol 156 (1) ◽  
pp. 230-242 ◽  
Author(s):  
F C de Beer ◽  
A K Soutar ◽  
M L Baltz ◽  
I M Trayner ◽  
A Feinstein ◽  
...  

C-reactive protein (CRP), the classical acute-phase protein, can bind phospholipids by virtue of its specific, calcium-dependent reactivity with phosphorylcholine residues. However, analysis of acute-phase serum by gel filtration and by density gradient ultracentrifugation showed that the CRP was in a free, uncomplexed form, despite the coexistent presence of the various classes of serum lipoproteins, all of which contain phospholipids. In contrast, when isolated CRP was aggregated by immobilization at a sufficient density on a solid phase and then exposed to normal human serum, it selectively bound low density lipoprotein (LDL) and traces of very low density lipoprotein. The reaction was calcium dependent and reversible by free phosphorylcholine but not by heparin. LDL isolated from normal plasma was also bound by aggregated CRP. CRP reacts in vitro with a wide variety of different ligands both of extrinsic and of autogenous origin, e.g., microbial products and damaged cell membranes, respectively. If CRP aggregated in vivo by complexing with these ligands than acquires the capacity to selectively bind LDL, the phenomenon may have significant implications for the function of CRP and for the metabolism, clearance, and deposition of LDL.


2016 ◽  
Vol 21 (1) ◽  
pp. 477-484 ◽  
Author(s):  
André Barbisan de Souza ◽  
Rogério T. P. Okawa ◽  
Cléverson O. Silva ◽  
Maurício G. Araújo

Hypertension ◽  
2012 ◽  
Vol 60 (suppl_1) ◽  
Author(s):  
Nicholas Parchim ◽  
Wei Wang ◽  
Chen Liu ◽  
Athar Siddiqui ◽  
Rodney Kellems ◽  
...  

Introduction: C-Reactive Protein (CRP) is an important immunomodulatory molecule. Early studies have indicated that CRP is elevated in preeclamptic patient sera, but its function remains unclear. CRP is known to bind with phosphocholine (PC) of bacteria membrane to kill bacteria by triggering innate immune response. Phosphocholination is a post-translational modification mediated by PC transferase, an enzyme reported expressed only in two tissues, including placenta and testis. Recent studies identified that Neurokinin B (NKB), a known, placenta-enriched pathogenic molecule for preeclampsia (PE), is phosphocholinated. This modification increases its stability, preferentially activates NK3 receptor (NK3R) and promotes PE features. Given CRP can bind to PC on bacterial membranes, the role that phosphocholination plays is a mystery. In light of NKB, being phosphocholinated in the endoplasmic reticulum and signals via the NK3R in the pathogenesis of PE, we feel that elevated CRP may be associated with NKB and contributes to the pathophysiology of PE via NK3R activation. Results: ELISA results show that CRP is significantly elevated in PE vs. control sera_65 ug/mL vs. 10 ug/ml; p<0.0001. Western blot analysis reveals that CRP, NKB, and NK3R are significantly increased in PE vs. control placental tissue. Immunohistochemistry studies indicate that all of these three molecules are abundant in syncytiotrophoblast cells. Co-immunoprecipitation demonstrates an interaction between CRP and NKB. In vitro , we provide the first evidence that CRP decreased the invasion of trophoblast cells from 0.7 ± 0.06 to 0.06 ± 0.001 invasion index; p<0.005, while treatment with SB222200 ameliorates shallow invasion from 0.28 ± 0.09 to 0.55 ± 0.07 invasion index; p<0.05. Significantly, infusion of CRP into pregnant mice induces hypertension (169.152 ± 14.7 mmHg vs. 141.916 ± 6.93 mmHg; p<0.05) and proteinuria (28.78 ± 13.56 mg albumin/μg Cr vs. 13.87 ± 3.277 mg albumin/μg Cr; p<0.05). Conclusion: Our findings demonstrate elevated CRP contributes to PE and NKB/NK3R is a new mechanism underlying CRP-mediated shallow invasion and disease development. These studies suggest novel pathogenic biomarkers and innovative therapies for PE.


2020 ◽  
Vol 37 (11) ◽  
pp. 2635-2641
Author(s):  
Fatemeh Diba-Bagtash ◽  
Azizeh Farshbaf-Khalili ◽  
Alyeh Ghasemzadeh ◽  
Laura Lotz ◽  
Amir Fattahi ◽  
...  

2015 ◽  
Vol 309 (12) ◽  
pp. H2098-H2107 ◽  
Author(s):  
Luis E. Okamoto ◽  
Satish R. Raj ◽  
Alfredo Gamboa ◽  
Cyndya A. Shibao ◽  
Amy C. Arnold ◽  
...  

Sympathetic activation is thought to contribute to the inflammatory process associated with obesity, which is characterized by elevated circulating C-reactive protein (hsCRP) and interleukin-6 (IL-6). To evaluate whether sympathetic activation is associated with inflammation in the absence of obesity, we studied patients with postural tachycardia syndrome (POTS), a condition characterized by increased sympathetic tone in otherwise healthy individuals. Compared with 23 lean controls, 43 lean female POTS had greater vascular sympathetic modulation (low-frequency blood pressure variability, LFSBP, 3.2 ± 0.4 vs. 5.5 ± 0.6 mmHg2, respectively, P = 0.006), lower cardiac parasympathetic modulation (high-frequency heart rate variability, 1,414 ± 398 vs. 369 ± 66 ms2, P = 0.001), and increased serum IL-6 (2.33 ± 0.49 vs. 4.15 ± 0.54 pg/ml, P = 0.011), but this was not associated with increases in hsCRP, which was low in both groups (0.69 ± 0.15 vs. 0.82 ± 0.16 mg/l, P = 0.736). To explore the contribution of adiposity to inflammation, we then compared 13 obese female POTS patients and 17 obese female controls to matched lean counterparts (13 POTS and 11 controls). Compared with lean controls, obese controls had increased LFSBP(3.3 ± 0.5 vs. 7.0 ± 1.1 mmHg2; P = 0.016), IL-6 (2.15 ± 0.58 vs. 3.92 ± 0.43 pg/ml; P = 0.030) and hsCRP (0.69 ± 0.20 vs. 3.47 ± 0.72 mg/l; P = 0.001). Obese and lean POTS had similarly high IL-6 but only obese POTS had increased hsCRP (5.76 ± 1.99 mg/l vs. 0.65 ± 0.26; P < 0.001). In conclusion, sympathetic activation in POTS is associated with increased IL-6 even in the absence of obesity. The coupling between IL-6 and CRP, however, requires increased adiposity, likely through release of IL-6 by visceral fat.


Sign in / Sign up

Export Citation Format

Share Document