title: NK cells and their receptors in naive and rituximab-treated patients with anti-MAG polyneuropathy.
abstract: BACKGROUND
  Natural killer (NK) cells can bridge innate and acquired immunity, and play a role in autoimmunity. A few studies evaluated the distribution of NK cells and the expression of their receptors in chronic immune-mediated demyelinating polyneuropathies. We investigated NK cell distribution and NK cell receptor expression in 20 naïve patients with anti-MAG polyneuropathy (MAG-PN).
  
  
  METHODS
  Using flow cytometry, we analysed NK cells and a series of NK cell receptors in the peripheral blood of patients with MAG-PN, and, as controls, in patients with chronic inflammatory demyelinating peripheral polyradiculoneuropathy (CIDP) and in healthy subjects. Six MAG-PN patients were also tested after rituximab treatment.
  
  
  RESULTS
  At baseline the percentage of NK cells did not differ among the groups. KIR2DL2 receptor expression in MAG-PN patients was higher, andCD94/NKG2A receptor expression in both MAG-PN and CIDP patients was lower than in healthy controls. These abnormalities did not correlate with any clinical or demographic variable. No modification was found after rituximab therapy.
  
  
  CONCLUSIONS
  The data suggest that MAG-PN shows abnormalities in NK cell receptors that characterise other autoimmune diseases, and cannot help in differential diagnosis with CIDP. The impairment of the relevant CD94/NKG2A inhibitory pathway, which might play a central role in the development and perpetuation of MAG-PN, warrants further functional investigations.
authors.affiliation: Department of Neurology, Osp. S. Andrea, La Spezia, Italy. luanabenedetti@libero.it
authors.forename: Luana
authors.initials: L
authors.lastname: Benedetti
authors.forename: Monica
authors.initials: M
authors.lastname: Facco
authors.forename: Diego
authors.initials: D
authors.lastname: Franciotta
authors.forename: Chiara
authors.initials: C
authors.lastname: Dalla Torre
authors.forename: Marta
authors.initials: M
authors.lastname: Campagnolo
authors.forename: Marta
authors.initials: M
authors.lastname: Lucchetta
authors.forename: Elisa
authors.initials: E
authors.lastname: Boscaro
authors.forename: Mario
authors.initials: M
authors.lastname: Ermani
authors.forename: Massimo
authors.initials: M
authors.lastname: Del Sette
authors.forename: Tamara
authors.initials: T
authors.lastname: Berno
authors.forename: Laura
authors.initials: L
authors.lastname: Candiotto
authors.forename: Renato
authors.initials: R
authors.lastname: Zambello
authors.forename: Chiara
authors.initials: C
authors.lastname: Briani
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D058846:Antibodies, Monoclonal, Murine-Derived / Q000627:therapeutic use*; D001323:Autoantibodies / Q000097:blood; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007155:Immunologic Factors / Q000627:therapeutic use*; D007694:Killer Cells, Natural / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D018992:Myelin-Associated Glycoprotein / Q000276:immunology*; D055654:NK Cell Lectin-Like Receptor Subfamily C / Q000378:metabolism; D051920:NK Cell Lectin-Like Receptor Subfamily D / Q000378:metabolism; D011115:Polyneuropathies / Q000276:immunology / Q000473:pathology / Q000628:therapy; D054343:Receptors, KIR2DL2 / Q000378:metabolism; D055607:Receptors, Natural Killer Cell / Q000378:metabolism*; D000069283:Rituximab
chemical_list: D058846:Antibodies, Monoclonal, Murine-Derived; D001323:Autoantibodies; D007155:Immunologic Factors; C497869:KLRD1 protein, human; D018992:Myelin-Associated Glycoprotein; D055654:NK Cell Lectin-Like Receptor Subfamily C; D051920:NK Cell Lectin-Like Receptor Subfamily D; D054343:Receptors, KIR2DL2; D055607:Receptors, Natural Killer Cell; D000069283:Rituximab
keywords: Anti-MAG antibodies; CD94/NKG2A; IgM; Monoclonal gammopathy; Myelin associated glycoprotein; Natural killer (NK) cells; Rituximab