title: Modulation of neutrophil apoptosis in plasma of patients after orthognathic surgery.
abstract: BACKGROUND
  Human neutrophils undergo rapid apoptosis during in vitro culture. The aim of this study was to investigate the role of interleukin-8 (IL-8) on neutrophil apoptosis in surgery-induced inflammation.
  
  
  METHODS
  Blood samples were drawn from 21 patients with mandibular prognathism 2 days before, and 1 and 5 days after orthognathic surgery. The IL-8 levels in the separated plasma were measured using an ELISA kit. The expression of two receptors for IL-8, CXCR1, and CXCR2, and their role in neutrophil apoptosis was evaluated using a flow cytometer.
  
  
  RESULTS
  The IL-8 levels in the plasma were correlated with acute inflammatory markers, such as peripheral blood neutrophil counts and C-reactive protein levels. Both IL-8 receptors were markedly raised in patient-derived neutrophils 1 day post-operatively. Recombinant IL-8 (0-100 ng/ml) suppressed apoptosis in fresh-isolated neutrophils from healthy donors dose-dependently. Neutrophil apoptosis 1 day post-operatively was slightly accelerated in the presence of fetal bovine serum compared to the value 2 days pre-operatively and 5 days post-operatively. In contrast, in the presence of autogenous plasma, neutrophil apoptosis was significantly suppressed 1 day post-operatively compared to the value 2 days pre-operatively and 5 days post-operatively. Moreover, the anti-apoptotic effect of plasma on neutrophil apoptosis was partially decreased by the addition of anti-IL-8 neutralizing antibody.
  
  
  CONCLUSIONS
  These results suggest that circulating neutrophils are susceptible to augmentation by IL-8 through the reinforcement of IL-8 receptors in acute inflammatory conditions. Furthermore, IL-8 may, in part, contribute to the regulation of neutrophil survival during the inflammatory response.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Showa University School of Dentistry, Tokyo, Japan.
authors.forename: Rikako
authors.initials: R
authors.lastname: Suzuki
authors.forename: Masayasu
authors.initials: M
authors.lastname: Iwase
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Miyaoka
authors.forename: Gen
authors.initials: G
authors.lastname: Kondo
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Watanabe
authors.forename: Masaru
authors.initials: M
authors.lastname: Ohashi
authors.forename: Masao
authors.initials: M
authors.lastname: Nagumo
mesh_terms: D000328:Adult; D000906:Antibodies / Q000276:immunology; D017209:Apoptosis / Q000187:drug effects / Q000276:immunology*; D002097:C-Reactive Protein / Q000378:metabolism; D005434:Flow Cytometry; D006801:Humans; D016209:Interleukin-8 / Q000097:blood / Q000276:immunology* / Q000494:pharmacology; D007958:Leukocyte Count; D009504:Neutrophils / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D019647:Oral Surgical Procedures; D011184:Postoperative Period; D023062:Receptors, Interleukin-8A / Q000378:metabolism; D023063:Receptors, Interleukin-8B / Q000378:metabolism; D013312:Stress, Physiological / Q000276:immunology
chemical_list: D000906:Antibodies; D016209:Interleukin-8; D023062:Receptors, Interleukin-8A; D023063:Receptors, Interleukin-8B; D002097:C-Reactive Protein