title: Soluble CD163 as a marker of macrophage activity in newly diagnosed patients with multiple sclerosis.
abstract: BACKGROUND
  Soluble CD163 (sCD163) is a macrophage specific protein known to be up-regulated in serum from patients with multiple sclerosis (MS).
  
  
  OBJECTIVE
  To investigate sCD163 in serum and CSF (cerebrospinal fluid) from patients undergoing MS diagnostic work-up and analyse its potential as a diagnostic biomarker.
  
  
  METHODS
  After a full MS diagnostic work-up, including collection of paired samples of CSF and serum, 183 patients were evaluated for inclusion in this study. Patients were divided into groups based on their diagnosis. Patients with normal clinical and paraclinical findings were grouped as symptomatic controls. Serum and CSF levels of sCD163 were determined by enzyme-linked immunosorbent assay (ELISA).
  
  
  RESULTS
  sCD163 could be measured in all serum and CSF samples. A high sCD163 CSF/serum ratio in relation to molecular weight was found, strongly indicating local production in the CNS. Median levels of sCD163 were significantly decreased in serum and significantly elevated in CSF in patients with relapsing-remitting, and primary-progressive MS. There were, however, some overlaps of the measures between groups. In a receiver operating characteristic (ROC) analysis sCD163 CSF/serum ratio had an area under the curve of 0.72.
  
  
  CONCLUSIONS
  The sCD163 CSF/serum ratio was significantly increased in patients with MS and may reflect macrophage activation in MS lesions. These results suggest that primary progressive MS also is driven by inflammation in which the innate immune system plays a pivotal role.
authors.affiliation: Department of Neurology, Aarhus University Hospital, Aarhus C, Denmark; Department of Biomedicine, Aarhus University, Aarhus C, Denmark.
authors.forename: Morten
authors.initials: M
authors.lastname: Stilund
authors.affiliation: Department of Clinical Biochemistry, Aarhus University Hospital, Aarhus C, Denmark.
authors.forename: Ann-Kathrin
authors.initials: AK
authors.lastname: Reuschlein
authors.affiliation: Department of Biomedicine, Aarhus University, Aarhus C, Denmark.
authors.forename: Tove
authors.initials: T
authors.lastname: Christensen
authors.affiliation: Department of Clinical Biochemistry, Aarhus University Hospital, Aarhus C, Denmark.
authors.forename: Holger Jon
authors.initials: HJ
authors.lastname: Møller
authors.affiliation: Department of Neurology, Aarhus University Hospital, Aarhus C, Denmark.
authors.forename: Peter Vestergaard
authors.initials: PV
authors.lastname: Rasmussen
authors.affiliation: Department of Neurology, Aarhus University Hospital, Aarhus C, Denmark.
authors.forename: Thor
authors.initials: T
authors.lastname: Petersen
mesh_terms: D015703:Antigens, CD / Q000378:metabolism*; D015214:Antigens, Differentiation, Myelomonocytic / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D008264:Macrophages / Q000378:metabolism*; D009103:Multiple Sclerosis / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000378:metabolism*; D000098902:CD163 Antigen
chemical_list: D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D000098902:CD163 Antigen; D011956:Receptors, Cell Surface