title: In vivo targeting of activated leukocytes by a β2-integrin binding peptide.
abstract: BACKGROUND
  In immunopathological conditions, clinical diagnosis is commonly made on the basis of patient symptoms, measurement of blood leukocyte levels or proinflammatory biomarkers, non-specific radiological findings and, regarding infection, microbiological analysis. Nevertheless, frequently the exact spatial location of inflammation or even infection cannot be reliably identified, despite the use of up-to-date clinical, laboratory and imaging techniques. For this reason, new tools are warranted for use in advanced diagnosis and therapy targeting in patients.
  
  
  OBJECTIVE
  The peptide CPCFLLGCC (LLG), known to bind activated β2-integrins in vitro, was fused with green fluorescent protein (GFP) to test the ability of LLG fusions to target and bind activated leukocytes in vivo.
  
  
  METHODS
  A murine skin scratch inflammation model was chosen for the convenient non-surgical detection of GFP.
  
  
  RESULTS
  The murine skin lesion inflammation model demonstrated in vivo targeting of LLG-GFP to sites of inflammation. Targeting by LLG-GFP fusion construct depends on the ability of the LLG-moiety to bind activated leukocytes. Control construct unable to bind β2-integrins appeared biologically inert.
  
  
  CONCLUSIONS
  The data support the possibility of using this fluorescently labeled peptide as a tool for both the detection of and targeting to inflammatory sites characterized by robust leukocyte activation.
authors: Division of Biochemistry and Biotechnology, Department of Biosciences, University of Helsinki, Helsinki, Finland.
authors: Tanja-Maria
authors: TM
authors: Ranta
authors: Juho
authors: J
authors: Suojanen
authors: Oula
authors: O
authors: Peñate-Medina
authors: Olga
authors: O
authors: Will
authors: Robert J
authors: RJ
authors: Tower
authors: Claus
authors: C
authors: Glüer
authors: Kalevi
authors: K
authors: Kairemo
authors: Carl G
authors: CG
authors: Gahmberg
authors: Erkki
authors: E
authors: Koivunen
authors: Timo
authors: T
authors: Sorsa
authors: Per E J
authors: PE
authors: Saris
authors: Justus
authors: J
authors: Reunanen
mesh_terms: D000818:Animals; D018821:CD18 Antigens / Q000276:immunology / Q000378:metabolism*; D002460:Cell Line; D004195:Disease Models, Animal; D016503:Drug Delivery Systems / Q000379:methods*; D006801:Humans; D007249:Inflammation / Q000276:immunology*; D007962:Leukocytes / Q000166:cytology* / Q000276:immunology / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D010455:Peptides / Q000737:chemistry* / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism*
chemical_list: D018821:CD18 Antigens; D010455:Peptides; D011993:Recombinant Fusion Proteins
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