title: A differential concentration-dependent effect of IVIg on neutrophil functions: relevance for anti-microbial and anti-inflammatory mechanisms.
abstract: BACKGROUND
  Polymorphonuclear neutrophils (PMN) play a key role in host defences against invading microorganisms but can also potentiate detrimental inflammatory reactions in case of excessive or misdirected responses. Intravenous immunoglobulins (IVIg) are used to treat patients with immune deficiencies and, at higher doses, in autoimmune, allergic and systemic inflammatory disorders.
  
  
  RESULTS
  We used flow cytometry to examine the effects of IVIg on PMN functions and survival, using whole-blood conditions in order to avoid artifacts due to isolation procedures. IVIg at low concentrations induced PMN activation, as reflected by decreased L-selectin and increased CD11b expression at the PMN surface, oxidative burst enhancement, and prolonged cell survival. In contrast, IVIg at higher concentrations inhibited LPS-induced CD11b degranulation and oxidative burst priming, and counteracted LPS-induced PMN lifespan prolongation.
  
  
  CONCLUSIONS
  IVIg appears to have differential, concentration-dependent effects on PMN, possibly supporting the use of IVIg as either an anti-microbial or an anti-inflammatory agent.
authors: Centre de Recherche des Cordeliers, Université Pierre et Marie Curie-Paris 6, UMR S 872, Paris, F-75006, France.
authors: Sarah
authors: S
authors: Casulli
authors: Selma
authors: S
authors: Topçu
authors: Lakhdar
authors: L
authors: Fattoum
authors: Stephan
authors: S
authors: von Gunten
authors: Hans-Uwe
authors: HU
authors: Simon
authors: Jean-Luc
authors: JL
authors: Teillaud
authors: Jagadeesh
authors: J
authors: Bayry
authors: Srini V
authors: SV
authors: Kaveri
authors: Carole
authors: C
authors: Elbim
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology*; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006801:Humans; D016756:Immunoglobulins, Intravenous / Q000494:pharmacology*; D008070:Lipopolysaccharides / Q000494:pharmacology; D018375:Neutrophil Activation / Q000187:drug effects; D009504:Neutrophils / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*
chemical_list: D000890:Anti-Infective Agents; D000893:Anti-Inflammatory Agents; D016756:Immunoglobulins, Intravenous; D008070:Lipopolysaccharides