title: Prominent plasmacytosis following intravenous immunoglobulin correlates with clinical improvement in Guillain-Barré syndrome.
abstract: BACKGROUND
  High doses of pooled polyclonal IgG are commonly used to treat numerous autoimmune diseases. Their mode of action nevertheless remains only partially explained. At the same time, until now, no early biological marker has been able to predict their efficacy.
  
  
  RESULTS
  In a first pilot retrospective analysis, we reviewed white blood cell counts and blood smears in consecutive patients with autoimmune disease (n = 202) and non-autoimmune disease (n = 104). Autoimmune patients received either intravenous immunoglobulin (IVIg, n = 103), plasma exchange (n = 78) or no specific treatment (n = 21). We then prospectively monitored consecutive autoimmune patients with IVIg injection (n = 67), or without any specific treatment (n = 10) using the same routine laboratory tests, as well as flow cytometry. Both retrospective and prospective analyses identified large plasma-cell mobilization exclusively in IVIg-treated autoimmune patients 7 days after initiation of treatment. The majority of IVIg-mobilized plasma cells were immature HLA-DR(high)/CD138(low)/CXCR4(low) plasma cells expressing intracellular immunoglobulin G which were neither IVIg- nor human IgG-specific. Importantly, we found a strong negative correlation between the absolute number of IVIg-mobilized plasma cells and time to improve neurological function in both retrospective and prospective studies of Guillain-Barré syndrome (GBS), (r = -0.52, p = 0.0031, n = 30, r = -0.47, p = 0.0028, n = 40, respectively).
  
  
  CONCLUSIONS
  IVIg promotes immature plasma-cell mobilization in patients with GBS, chronic inflammatory demyelinating polyneuropathy, myasthenia gravis and inflammatory myopathy. Prominent day 7 plasma-cell mobilization is a favourable prognostic marker in patients with GBS receiving IVIg treatment.
authors.affiliation: Institut National de la Santé et de la Recherche Médicale (INSERM) U543, Paris, France.
authors.forename: Izumi
authors.initials: I
authors.lastname: Mori
authors.forename: Christophe
authors.initials: C
authors.lastname: Parizot
authors.forename: Karim
authors.initials: K
authors.lastname: Dorgham
authors.forename: Sophie
authors.initials: S
authors.lastname: Demeret
authors.forename: Zahir
authors.initials: Z
authors.lastname: Amoura
authors.forename: Francis
authors.initials: F
authors.lastname: Bolgert
authors.forename: Guy
authors.initials: G
authors.lastname: Gorochov
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002470:Cell Survival / Q000187:drug effects; D005260:Female; D020275:Guillain-Barre Syndrome / Q000276:immunology* / Q000473:pathology; D006801:Humans; D016756:Immunoglobulins, Intravenous / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D010950:Plasma Cells / Q000166:cytology / Q000187:drug effects / Q000276:immunology / Q000473:pathology*; D012016:Reference Values; D012189:Retrospective Studies; D012720:Severity of Illness Index
chemical_list: D016756:Immunoglobulins, Intravenous