title: Molecular Imaging with Kupffer Cell-Targeting Nanobodies for Diagnosis and Prognosis in Mouse Models of Liver Pathogenesis.
abstract: Kupffer cells (KCs), the liver resident macrophages, are important mediators of tissue homeostasis and pathogen clearance. However, depending on the inflammatory stimuli, KCs have been involved in divergent hepato-protective or hepato-destructive immune responses. The versatility of KCs in response to environmental triggers, in combination with the specific biomarkers they express, make these macrophages attractive in vivo targets for non-invasive monitoring of liver inflammation or pathogenicity. This study aims to determine whether V-set and Ig domain-containing 4 (Vsig4) and C-type lectin domain family (Clec) 4, member F (Clec4F) can be used as imaging biomarkers for non-invasive monitoring of KCs during distinct liver inflammation models.
  
  
  
  Flow cytometry (FACS), immuno-histochemistry (IHC), and single-photon emission computed tomography (SPECT) with Tc-99m labeled anti-Vsig4 or anti-Clec4F nanobodies (Nbs) was performed to evaluate in mice KC dynamics in concanavalin A (ConA)-induced hepatitis and in non-alcoholic steatohepatitis induced via methionine choline deficiency (MCD).
  
  
  
  In homeostatic mice, Nbs targeting Clec4F were found to accumulate and co-localize with Vsig4-targeting Nbs only in the liver. Upon induction of acute hepatitis using ConA, down-regulation of the in vivo Nb imaging signal was observed, reflecting reduction in KC numbers as confirmed by FACS and IHC. On the other hand, induction of steatohepatitis resulted in higher signals in the liver corresponding to higher density of KCs. The Nb-imaging signals returned to normal levels after resolution of the investigated liver diseases.
  
  
  
  Anti-Clec4F and anti-Vsig4 Nbs targeting KCs as molecular imaging biomarkers could allow non-invasive monitoring/staging of liver pathogenesis.
authors.affiliation: Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Pleinlaan 2, Building E, 8th floor, Brussels, Belgium.|Myeloid Cell Immunology Laboratory, VIB Inflammation Research Center, Ghent, Belgium.
authors.forename: Fang
authors.initials: F
authors.lastname: Zheng
authors.affiliation: Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Pleinlaan 2, Building E, 8th floor, Brussels, Belgium.|Myeloid Cell Immunology Laboratory, VIB Inflammation Research Center, Ghent, Belgium.
authors.forename: Amanda
authors.initials: A
authors.lastname: Sparkes
authors.affiliation: Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Pleinlaan 2, Building E, 8th floor, Brussels, Belgium.|Myeloid Cell Immunology Laboratory, VIB Inflammation Research Center, Ghent, Belgium.
authors.forename: Patrick
authors.initials: P
authors.lastname: De Baetselier
authors.affiliation: Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Pleinlaan 2, Building E, 8th floor, Brussels, Belgium.|Myeloid Cell Immunology Laboratory, VIB Inflammation Research Center, Ghent, Belgium.
authors.forename: Steve
authors.initials: S
authors.lastname: Schoonooghe
authors.affiliation: Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Pleinlaan 2, Building E, 8th floor, Brussels, Belgium.|Myeloid Cell Immunology Laboratory, VIB Inflammation Research Center, Ghent, Belgium.
authors.forename: Benoit
authors.initials: B
authors.lastname: Stijlemans
authors.affiliation: Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Pleinlaan 2, Building E, 8th floor, Brussels, Belgium.
authors.forename: Serge
authors.initials: S
authors.lastname: Muyldermans
authors.affiliation: Institute of Medical Immunology, ULB, Gosselies, Belgium.
authors.forename: Véronique
authors.initials: V
authors.lastname: Flamand
authors.affiliation: Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Pleinlaan 2, Building E, 8th floor, Brussels, Belgium.|Myeloid Cell Immunology Laboratory, VIB Inflammation Research Center, Ghent, Belgium.
authors.forename: Jo A
authors.initials: JA
authors.lastname: Van Ginderachter
authors.affiliation: In Vivo Cellular and Molecular Imaging Center, VUB, Brussels, Belgium.
authors.forename: Nick
authors.initials: N
authors.lastname: Devoogdt
authors.affiliation: Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Pleinlaan 2, Building E, 8th floor, Brussels, Belgium.|Myeloid Cell Immunology Laboratory, VIB Inflammation Research Center, Ghent, Belgium.
authors.forename: Geert
authors.initials: G
authors.lastname: Raes
authors.affiliation: Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Pleinlaan 2, Building E, 8th floor, Brussels, Belgium. Alain.Beschin@vib-vub.be.|Myeloid Cell Immunology Laboratory, VIB Inflammation Research Center, Ghent, Belgium. Alain.Beschin@vib-vub.be.
authors.forename: Alain
authors.initials: A
authors.lastname: Beschin
mesh_terms: D000818:Animals; D039481:CD11b Antigen / Q000378:metabolism; D002452:Cell Count; D002794:Choline; D003208:Concanavalin A; D004195:Disease Models, Animal; D019693:Hepatitis, Autoimmune / Q000473:pathology; D007728:Kupffer Cells / Q000378:metabolism*; D037181:Lectins, C-Type / Q000378:metabolism; D008099:Liver / Q000378:metabolism / Q000473:pathology*; D008297:Male; D008715:Methionine / Q000172:deficiency; D008810:Mice, Inbred C57BL; D057054:Molecular Imaging / Q000379:methods*; D011379:Prognosis; D061905:Single-Domain Antibodies / Q000737:chemistry*; D014018:Tissue Distribution
chemical_list: D039481:CD11b Antigen; C585570:CLEC4F protein, mouse; D037181:Lectins, C-Type; D061905:Single-Domain Antibodies; D003208:Concanavalin A; D008715:Methionine; D002794:Choline
keywords: C-type lectin domain family, 4 member F (Clec4F); Concanavalin A; Hepatitis; Methionine choline deficiency (MCD); Nanobodies (Nbs); Steatohepatitis; V-set and immunoglobulin domain-containing 4 (Vsig4)