title: Dissociation of pentameric to monomeric C-reactive protein localizes and aggravates inflammation: in vivo proof of a powerful proinflammatory mechanism and a new anti-inflammatory strategy.
abstract: BACKGROUND
  The relevance of the dissociation of circulating pentameric C-reactive protein (pCRP) to its monomeric subunits (mCRP) is poorly understood. We investigated the role of conformational C-reactive protein changes in vivo.
  
  
  RESULTS
  We identified mCRP in inflamed human striated muscle, human atherosclerotic plaque, and infarcted myocardium (rat and human) and its colocalization with inflammatory cells, which suggests a general causal role of mCRP in inflammation. This was confirmed in rat intravital microscopy of lipopolysaccharide-induced cremasteric muscle inflammation. Intravenous pCRP administration significantly enhanced leukocyte rolling, adhesion, and transmigration via localized dissociation to mCRP in inflamed but not noninflamed cremaster muscle. This was confirmed in a rat model of myocardial infarction. Mechanistically, this process was dependent on exposure of lysophosphatidylcholine on activated cell membranes, which is generated after phospholipase A2 activation. These membrane changes could be visualized intravitally on endothelial cells, as could the colocalized mCRP generation. Blocking of phospholipase A2 abrogated C-reactive protein dissociation and thereby blunted the proinflammatory effects of C-reactive protein. Identifying the dissociation process as a therapeutic target, we stabilized pCRP using 1,6-bis(phosphocholine)-hexane, which prevented dissociation in vitro and in vivo and consequently inhibited the generation and proinflammatory activity of mCRP; notably, it also inhibited mCRP deposition and inflammation in rat myocardial infarction.
  
  
  CONCLUSIONS
  These results provide in vivo evidence for a novel mechanism that localizes and aggravates inflammation via phospholipase A2-dependent dissociation of circulating pCRP to mCRP. mCRP is proposed as a pathogenic factor in atherosclerosis and myocardial infarction. Most importantly, the inhibition of pCRP dissociation represents a promising, novel anti-inflammatory therapeutic strategy.
authors: From the University of Freiburg Medical Center, Department of Plastic and Hand Surgery (J.R.T., D.B., Y.S., K.G., V.M., H.B., G.B.S., S.U.E.) and Section of Endocrine Surgery, Clinic of General, Visceral and Thoracic Surgery, Academic Teaching Hospital University of Hamburg (E.v.D.), Reinbeck, Germany; Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (J.H., A.S., K.P.); Imperial College London, Department of Medicine, London, United Kingdom (K.J.W.); and CVPath Institute, Gaithersburg, MD (F.K., R.V.).
authors: Jan R
authors: JR
authors: Thiele
authors: From the University of Freiburg Medical Center, Department of Plastic and Hand Surgery (J.R.T., D.B., Y.S., K.G., V.M., H.B., G.B.S., S.U.E.) and Section of Endocrine Surgery, Clinic of General, Visceral and Thoracic Surgery, Academic Teaching Hospital University of Hamburg (E.v.D.), Reinbeck, Germany; Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (J.H., A.S., K.P.); Imperial College London, Department of Medicine, London, United Kingdom (K.J.W.); and CVPath Institute, Gaithersburg, MD (F.K., R.V.).
authors: Jonathon
authors: J
authors: Habersberger
authors: From the University of Freiburg Medical Center, Department of Plastic and Hand Surgery (J.R.T., D.B., Y.S., K.G., V.M., H.B., G.B.S., S.U.E.) and Section of Endocrine Surgery, Clinic of General, Visceral and Thoracic Surgery, Academic Teaching Hospital University of Hamburg (E.v.D.), Reinbeck, Germany; Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (J.H., A.S., K.P.); Imperial College London, Department of Medicine, London, United Kingdom (K.J.W.); and CVPath Institute, Gaithersburg, MD (F.K., R.V.).
authors: David
authors: D
authors: Braig
authors: From the University of Freiburg Medical Center, Department of Plastic and Hand Surgery (J.R.T., D.B., Y.S., K.G., V.M., H.B., G.B.S., S.U.E.) and Section of Endocrine Surgery, Clinic of General, Visceral and Thoracic Surgery, Academic Teaching Hospital University of Hamburg (E.v.D.), Reinbeck, Germany; Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (J.H., A.S., K.P.); Imperial College London, Department of Medicine, London, United Kingdom (K.J.W.); and CVPath Institute, Gaithersburg, MD (F.K., R.V.).
authors: Yvonne
authors: Y
authors: Schmidt
authors: From the University of Freiburg Medical Center, Department of Plastic and Hand Surgery (J.R.T., D.B., Y.S., K.G., V.M., H.B., G.B.S., S.U.E.) and Section of Endocrine Surgery, Clinic of General, Visceral and Thoracic Surgery, Academic Teaching Hospital University of Hamburg (E.v.D.), Reinbeck, Germany; Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (J.H., A.S., K.P.); Imperial College London, Department of Medicine, London, United Kingdom (K.J.W.); and CVPath Institute, Gaithersburg, MD (F.K., R.V.).
authors: Kurt
authors: K
authors: Goerendt
authors: From the University of Freiburg Medical Center, Department of Plastic and Hand Surgery (J.R.T., D.B., Y.S., K.G., V.M., H.B., G.B.S., S.U.E.) and Section of Endocrine Surgery, Clinic of General, Visceral and Thoracic Surgery, Academic Teaching Hospital University of Hamburg (E.v.D.), Reinbeck, Germany; Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (J.H., A.S., K.P.); Imperial College London, Department of Medicine, London, United Kingdom (K.J.W.); and CVPath Institute, Gaithersburg, MD (F.K., R.V.).
authors: Valentin
authors: V
authors: Maurer
authors: From the University of Freiburg Medical Center, Department of Plastic and Hand Surgery (J.R.T., D.B., Y.S., K.G., V.M., H.B., G.B.S., S.U.E.) and Section of Endocrine Surgery, Clinic of General, Visceral and Thoracic Surgery, Academic Teaching Hospital University of Hamburg (E.v.D.), Reinbeck, Germany; Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (J.H., A.S., K.P.); Imperial College London, Department of Medicine, London, United Kingdom (K.J.W.); and CVPath Institute, Gaithersburg, MD (F.K., R.V.).
authors: Holger
authors: H
authors: Bannasch
authors: From the University of Freiburg Medical Center, Department of Plastic and Hand Surgery (J.R.T., D.B., Y.S., K.G., V.M., H.B., G.B.S., S.U.E.) and Section of Endocrine Surgery, Clinic of General, Visceral and Thoracic Surgery, Academic Teaching Hospital University of Hamburg (E.v.D.), Reinbeck, Germany; Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (J.H., A.S., K.P.); Imperial College London, Department of Medicine, London, United Kingdom (K.J.W.); and CVPath Institute, Gaithersburg, MD (F.K., R.V.).
authors: Amelie
authors: A
authors: Scheichl
authors: From the University of Freiburg Medical Center, Department of Plastic and Hand Surgery (J.R.T., D.B., Y.S., K.G., V.M., H.B., G.B.S., S.U.E.) and Section of Endocrine Surgery, Clinic of General, Visceral and Thoracic Surgery, Academic Teaching Hospital University of Hamburg (E.v.D.), Reinbeck, Germany; Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (J.H., A.S., K.P.); Imperial College London, Department of Medicine, London, United Kingdom (K.J.W.); and CVPath Institute, Gaithersburg, MD (F.K., R.V.).
authors: Kevin J
authors: KJ
authors: Woollard
authors: From the University of Freiburg Medical Center, Department of Plastic and Hand Surgery (J.R.T., D.B., Y.S., K.G., V.M., H.B., G.B.S., S.U.E.) and Section of Endocrine Surgery, Clinic of General, Visceral and Thoracic Surgery, Academic Teaching Hospital University of Hamburg (E.v.D.), Reinbeck, Germany; Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (J.H., A.S., K.P.); Imperial College London, Department of Medicine, London, United Kingdom (K.J.W.); and CVPath Institute, Gaithersburg, MD (F.K., R.V.).
authors: Ernst
authors: E
authors: von Dobschütz
authors: From the University of Freiburg Medical Center, Department of Plastic and Hand Surgery (J.R.T., D.B., Y.S., K.G., V.M., H.B., G.B.S., S.U.E.) and Section of Endocrine Surgery, Clinic of General, Visceral and Thoracic Surgery, Academic Teaching Hospital University of Hamburg (E.v.D.), Reinbeck, Germany; Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (J.H., A.S., K.P.); Imperial College London, Department of Medicine, London, United Kingdom (K.J.W.); and CVPath Institute, Gaithersburg, MD (F.K., R.V.).
authors: Frank
authors: F
authors: Kolodgie
authors: From the University of Freiburg Medical Center, Department of Plastic and Hand Surgery (J.R.T., D.B., Y.S., K.G., V.M., H.B., G.B.S., S.U.E.) and Section of Endocrine Surgery, Clinic of General, Visceral and Thoracic Surgery, Academic Teaching Hospital University of Hamburg (E.v.D.), Reinbeck, Germany; Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (J.H., A.S., K.P.); Imperial College London, Department of Medicine, London, United Kingdom (K.J.W.); and CVPath Institute, Gaithersburg, MD (F.K., R.V.).
authors: Renu
authors: R
authors: Virmani
authors: From the University of Freiburg Medical Center, Department of Plastic and Hand Surgery (J.R.T., D.B., Y.S., K.G., V.M., H.B., G.B.S., S.U.E.) and Section of Endocrine Surgery, Clinic of General, Visceral and Thoracic Surgery, Academic Teaching Hospital University of Hamburg (E.v.D.), Reinbeck, Germany; Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (J.H., A.S., K.P.); Imperial College London, Department of Medicine, London, United Kingdom (K.J.W.); and CVPath Institute, Gaithersburg, MD (F.K., R.V.).
authors: G Bjoern
authors: GB
authors: Stark
authors: From the University of Freiburg Medical Center, Department of Plastic and Hand Surgery (J.R.T., D.B., Y.S., K.G., V.M., H.B., G.B.S., S.U.E.) and Section of Endocrine Surgery, Clinic of General, Visceral and Thoracic Surgery, Academic Teaching Hospital University of Hamburg (E.v.D.), Reinbeck, Germany; Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (J.H., A.S., K.P.); Imperial College London, Department of Medicine, London, United Kingdom (K.J.W.); and CVPath Institute, Gaithersburg, MD (F.K., R.V.).
authors: Karlheinz
authors: K
authors: Peter
authors: From the University of Freiburg Medical Center, Department of Plastic and Hand Surgery (J.R.T., D.B., Y.S., K.G., V.M., H.B., G.B.S., S.U.E.) and Section of Endocrine Surgery, Clinic of General, Visceral and Thoracic Surgery, Academic Teaching Hospital University of Hamburg (E.v.D.), Reinbeck, Germany; Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (J.H., A.S., K.P.); Imperial College London, Department of Medicine, London, United Kingdom (K.J.W.); and CVPath Institute, Gaithersburg, MD (F.K., R.V.). steffen.eisenhardt@uniklinik-freiburg.de.
authors: Steffen U
authors: SU
authors: Eisenhardt
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology / Q000627:therapeutic use; D001704:Biopolymers; D002097:C-Reactive Protein / Q000737:chemistry* / Q000502:physiology; D002352:Carrier Proteins / Q000737:chemistry* / Q000502:physiology; D002448:Cell Adhesion / Q000187:drug effects; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D002634:Chemotaxis, Leukocyte; D003167:Complement Activation; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism; D006586:Hexanes / Q000494:pharmacology / Q000627:therapeutic use; D006801:Humans; D007249:Inflammation / Q000188:drug therapy / Q000209:etiology / Q000378:metabolism*; D036904:Leukocyte Rolling / Q000187:drug effects; D008070:Lipopolysaccharides / Q000633:toxicity; D008244:Lysophosphatidylcholines / Q000378:metabolism; D008297:Male; D008563:Membrane Lipids / Q000378:metabolism; D018482:Muscle, Skeletal / Q000098:blood supply / Q000378:metabolism*; D009203:Myocardial Infarction / Q000378:metabolism* / Q000473:pathology; D009220:Myositis / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology; D064801:Phospholipase A2 Inhibitors / Q000494:pharmacology / Q000627:therapeutic use; D054467:Phospholipases A2 / Q000378:metabolism; D010767:Phosphorylcholine / Q000031:analogs & derivatives / Q000494:pharmacology / Q000627:therapeutic use; D020836:Protein Structure, Quaternary; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D017452:Receptors, IgG / Q000502:physiology; D015427:Reperfusion Injury / Q000378:metabolism / Q000473:pathology
chemical_list: C510236:1,6-bis(phosphocholine)-hexane; D000893:Anti-Inflammatory Agents; D001704:Biopolymers; D002352:Carrier Proteins; C030929:Crp protein, rat; D006586:Hexanes; D008070:Lipopolysaccharides; D008244:Lysophosphatidylcholines; D008563:Membrane Lipids; D064801:Phospholipase A2 Inhibitors; D017452:Receptors, IgG; D010767:Phosphorylcholine; D002097:C-Reactive Protein; D054467:Phospholipases A2
keywords: C-reactive protein; atherosclerosis; inflammation; microcirculation; myocardial infarction