title: SIGLEC1 and SIGLEC7 expression in circulating monocytes of patients with multiple sclerosis.
abstract: BACKGROUND
  Sialic acid binding immunoglobulin-like lectins (Siglecs) are cell surface receptors that recognize sialic acids and may attenuate immune responses and reduce inflammation.
  
  
  OBJECTIVE
  The purpose of this study was to investigate the role of two members of the Siglec family, SIGLEC1 and SIGLEC7, in the clinical course and disease activity of patients with multiple sclerosis (MS).
  
  
  METHODS
  SIGLEC1 and SIGLEC7 expression was determined by flow cytometry in the blood monocytes of 16 healthy controls and 55 untreated MS patients (13 primary progressive MS (PPMS) patients, 13 secondary progressive MS (SPMS) patients and 29 relapsing-remitting MS (RRMS) patients (18 during clinical remission and 11 during relapse)).
  
  
  RESULTS
  SIGLEC1 expression by CD14+ monocytes was significantly increased in MS patients compared with controls (p=0.025 for percentage of positive cells; p=0.007 for mean fluorescence intensity (MFI)). Stratification of patients into different clinical forms revealed increased SIGLEC1 expression in patients with progressive forms of the disease, particularly in those with PPMS (p=0.003 for percentage of positive cells and p=0.001 for MFI when compared with controls; p=0.031 for percentage of positive cells when compared with RRMS patients). Both inflammatory and resident monocytes contributed to the increase in SIGLEC1 expression observed in PPMS patients. SIGLEC7 expression was significantly up-regulated in blood monocytes from RRMS during relapse compared with patients during clinical remission (p=0.001 for MFI).
  
  
  CONCLUSIONS
  These findings suggest roles for SIGLEC1 in the chronic progressive phases of MS and for SIGLEC7 in acute disease activity.
authors.affiliation: Centre d'Esclerosi Múltiple de Catalunya, Hospital Universitari Vall d'Hebron, Spain.
authors.forename: S
authors.initials: S
authors.lastname: Malhotra
authors.forename: J
authors.initials: J
authors.lastname: Castilló
authors.forename: Mf
authors.initials: M
authors.lastname: Bustamante
authors.forename: A
authors.initials: A
authors.lastname: Vidal-Jordana
authors.forename: Z
authors.initials: Z
authors.lastname: Castro
authors.forename: X
authors.initials: X
authors.lastname: Montalban
authors.forename: M
authors.initials: M
authors.lastname: Comabella
mesh_terms: D000328:Adult; D015214:Antigens, Differentiation, Myelomonocytic / Q000378:metabolism*; D016022:Case-Control Studies; D018450:Disease Progression; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D037102:Lectins / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism*; D009103:Multiple Sclerosis / Q000378:metabolism*; D020528:Multiple Sclerosis, Chronic Progressive / Q000378:metabolism; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000378:metabolism; D063267:Sialic Acid Binding Ig-like Lectin 1 / Q000378:metabolism*; D055815:Young Adult
chemical_list: D015214:Antigens, Differentiation, Myelomonocytic; D037102:Lectins; C571166:SIGLEC1 protein, human; C402206:SIGLEC7 protein, human; D063267:Sialic Acid Binding Ig-like Lectin 1