Expression of membrane-associated C-reactive protein by human monocytes: indications for a selectin-like activity participating in adhesion

Kolb-Bachofen, Victoria; Puchta-Teudt, Nicola; Egenhofer, Christine

doi:10.1007/bf00731355

Cited by 29 publications

(12 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The biochemical properties of the free subunits of CRP formed in vivo have not yet been described. Intriguingly, mCRP cross-reactive epitopes have been reported in vascular tissues (23), inflamed rabbit liver and muscle (22), monocytes (40), and islet cells (41). In addition, the genetic message for CRP subunit is expressed in peripheral blood mononuclear cells (40,42), alveolar macrophages (43), islet cells (41), and epithelial cells of the respiratory tract (44).…”

Section: Discussionmentioning

confidence: 99%

“…Intriguingly, mCRP cross-reactive epitopes have been reported in vascular tissues (23), inflamed rabbit liver and muscle (22), monocytes (40), and islet cells (41). In addition, the genetic message for CRP subunit is expressed in peripheral blood mononuclear cells (40,42), alveolar macrophages (43), islet cells (41), and epithelial cells of the respiratory tract (44). Hence, the mCRP used in the present studies may be similar, if not identical, to a naturally occurring isomeric form of CRP found in various tissues and cells throughout the body.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Loss of Pentameric Symmetry of C-reactive Protein Is Associated with Delayed Apoptosis of Human Neutrophils

Khreiss

József

Hossain

et al. 2002

Journal of Biological Chemistry

147

164

View full text Add to dashboard Cite

Human neutrophil granulocytes die rapidly, and their survival is contingent upon rescue from programmed cell death by signals from the environment. Here we report that a novel signal for delaying neutrophil apoptosis is the classic acute phase reactant, C-reactive protein (CRP). However, this anti-apoptotic activity is expressed only when the cyclic pentameric structure of CRP is lost, resulting in formation of modified or monomeric CRP (mCRP), which may be formed in inflamed tissues. By contrast, native pentameric CRP and CRP peptides 77-82, 174 -185, and 201-206 failed to affect neutrophil apoptosis. The apoptosis delaying action of mCRP was markedly attenuated by an antibody against the low affinity IgG immune complex receptor (CD16) but not by an anti-CD32 antibody. mCRP evoked a transient concurrent activation of the extracellular signalregulated kinase (ERK) and phosphatidylinositol 3-kinase/Akt signaling pathways, leading to inhibition of caspase-3 and consequently to delaying apoptosis. Consistently, pharmacological inhibition of either ERK or Akt reversed the anti-apoptotic action of mCRP; however, they did not produce additive inhibition. Thus, mCRP, but not pentameric CRP or peptides derived from CRP, promotes neutrophil survival and may therefore contribute to amplification of the inflammatory response.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Loss of Pentameric Symmetry of C-reactive Protein Is Associated with Delayed Apoptosis of Human Neutrophils

Khreiss

József

Hossain

et al. 2002

Journal of Biological Chemistry

147

164

View full text Add to dashboard Cite

show abstract

“…The -modified‖ subunits tend to self-aggregate (15)(16)(17). Antigens cross-reactive with its distinctive antigenicity have been found in various tissues or cells or as a membrane-bound protein (i.e., tissue-based CRP) (8,12,(18)(19)(20)(21). In vitro, mCRP can be produced from nCRP by exposing nCRP to heat, urea, or acidic conditions, generally in the absence of calcium ions (17).…”

mentioning

confidence: 99%

Production of Modified C-Reactive Protein in U937-Derived Macrophages

Ciubotaru

Potempa

Wander

2005

Exp Biol Med (Maywood)

View full text Add to dashboard Cite

Abstract:Plasma C-reactive protein (CRP) has been proposed to be a strong independent predictor for cardiovascular disease. This circulating form of CRP (native CRP or nCRP) is well described. Recently, the existence of a conformationally distinct isoform of CRP (modified CRP or mCRP) has been reported. The relevance of each CRP isoform to atherosclerotic disease is unknown. The purpose of this study was to examine the natural expression of CRP in undifferentiated, differentiated, and stimulated macrophages, cells known to contribute to atherogenesis in vivo, and to determine whether transcribed CRP was expressed as nCRP or mCRP. Macrophages were generated from U937 monocytes using phorbol 12-myristate 13-acetate. Differentiated macrophages were further stimulated with lipopolysaccharides (LPS). In undifferentiated, differentiated, and stimulated cells, CRP expression was assessed by reverse transcriptionpolymerase chain reaction, and CRP protein production was measured by fluorescence microscopy and flow cytometry (cellular CRP) or high-sensitivity enzyme-linked immunosorbent assay (secreted CRP). CRP transcript was minimally expressed in undifferentiated cells. Expression increased markedly in macrophages during differentiation and was not affected by LPS at 24 hrs. Cellular CRP protein increased in a time-dependent manner after LPS stimulation, and this induction was mediated via interleukin (IL)-6 and IL-1p. A small amount of secreted CRP was detected in the media of differentiated cells, but it was not significantly increased after LPS stimulation. Using specific monoclonal antibodies, our data indicate that cellular CRP is directly translated as the mCRP rather than the nCRP isomer. These results indicate that U937-derived macrophages are a good cell model to further study the production of mCRP under conditions relevant for the atherogenic process. Exp Biol Med 230:762-770, 2005 Article: Seven decades after its discovery, the acute-phase protein C-reactive protein (CRP) has emerged as a strong predictor for cardiovascular disease. These observations have accumulated as highly sensitive assays for the measurement of previously undetectable concentrations of circulating CRP became commercially available. Hence, low concentrations of CRP are sometimes denoted as high-sensitivity CRP (hs-CRP) to indicate the use of such assays. Recent studies conducted in healthy men and women indicate that plasma CRP concentrations as low as 1-3 gg/ml may

show abstract

“…Physiologically, membrane association of CRP to Kupffer cells and monocytes can be an equivalent of the special in vitro situation. The monocyte surface CRP is immunologically distinguishable from the circulating form, it is capable of mediating uptake of lactoseexposing particles and is also crucial for the sugar-inhibitable adhesion to immobilized fibronectin (Egenhofer et al, 1993 ;Kolb-Bachofen et al, 1995). The initial carbohydrate-dependent contact is then followed by a peptide-specific recognition via integrin receptors, as similarly documented for selectins, galectin-3 and calreticulin.…”

Section: Pentraxinsmentioning

confidence: 90%

Animal Lectins

Gabius

1997

European Journal of Biochemistry

435

342

View full text Add to dashboard Cite

Protein and lipid glycosylation is no longer considered as a topic whose appeal is restricted to a limited number of analytical experts perseveringly pursuing the comprehensive cataloguing of structural variants. It is in fact arousing curiosity in various areas of basic and applied bioscience. Well founded by the conspicuous coding potential of the sugar part of cellular glycoconjugates which surpasses the storage capacity of oligonucleotide-or oligopeptide-based code systems, recognition of distinct oligosaccharide ligands by endogenous receptors, i.e. lectins and sugar-binding enzymes or antibodies, is increasingly being discovered to play salient roles in animal physiology. Having inevitably started with a descriptive stage, research on animal lectins has now undubitably reached maturity. Besides listing the current categories for lectin classification and providing presentations of the individual families and their presently delineated physiological significance, this review places special emphasis on tracing common structural and functional themes which appear to reverberate in nominally separated lectin and animal categories as well as lines of research which may come to fruition for medical sciences.Keywords: lectin ; glycoprotein; glycolipid; cell adhesion ; molecular recognition ; inflammation; infection ; fertilization ; signal transduction ; tumor biology.The putative multiplicity of functional implications for protein and lipid glycosylation has fueled vigorous and prolific research activities in the last decade. Although glycobiologists continue to be afflicted with the problem of precisely defining the physiological significance of the puzzling variability and complex pattern of carrier-attached saccharide chains, the notion of inherent ligand properties for recognitive protein-carbohydrate interactions is already well established

show abstract

Expression of membrane-associated C-reactive protein by human monocytes: indications for a selectin-like activity participating in adhesion

Cited by 29 publications

References 26 publications

Loss of Pentameric Symmetry of C-reactive Protein Is Associated with Delayed Apoptosis of Human Neutrophils

Loss of Pentameric Symmetry of C-reactive Protein Is Associated with Delayed Apoptosis of Human Neutrophils

Production of Modified C-Reactive Protein in U937-Derived Macrophages

Animal Lectins

Contact Info

Product

Resources

About