title: Tumor necrosis factor-α-induced mononuclear cell death may contribute to polymorphonuclear cell predominance in the cerebrospinal fluid of patients with bacterial meningitis.
abstract: BACKGROUND
  Bacterial meningitis is characterized by a marked predominance of polymorphonuclear leukocytes (PMNs: segmented granulocytes or neutrophils) in the cerebrospinal fluid (CSF), whereas aseptic meningitis is characterized by a predominance of mononuclear leukocytes (MNs: lymphocytes or monocytes). However, the pathophysiology of this predominance of PMNs in the CSF of patients with bacterial meningitis has never, to our knowledge, been clearly described.
  
  
  METHODS
  To investigate the predominant cell components of CSF from pediatric patients with bacterial meningitis, we investigated cell death in association with levels of tumor necrosis factor-alpha (TNF-α) in the CSF, using the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide) assay and flow cytometry.
  
  
  RESULTS
  The MTT assay of the CSF revealed that the PMNs had survived, while the MNs rapidly had undergone cell death. Although PMNs survived in CSF with high levels of TNF-α, PMN apoptosis was demonstrated with flow cytometry.
  
  
  CONCLUSIONS
  The present study suggests that the pathophysiology of PMN predominance in the CSF of patients in the acute phase of bacterial meningitis is related to the rapid cell death of MNs and the survival of PMNs brought about by high levels of TNF-α.
authors.affiliation: Department of Pediatrics, Nippon Medical School, Tama, Tokyo, Japan. kawakami@nms.ac.jp
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Kawakami
authors.forename: Mitsutoshi
authors.initials: M
authors.lastname: Tsukimoto
authors.forename: Kentaro
authors.initials: K
authors.lastname: Kuwabara
authors.forename: Takehisa
authors.initials: T
authors.lastname: Fujita
authors.forename: Osamu
authors.initials: O
authors.lastname: Fujino
authors.forename: Shuji
authors.initials: S
authors.lastname: Kojima
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Fukunaga
mesh_terms: D016923:Cell Death; D002555:Cerebrospinal Fluid / Q000166:cytology*; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007963:Leukocytes, Mononuclear / Q000473:pathology*; D008297:Male; D016920:Meningitis, Bacterial / Q000209:etiology* / Q000473:pathology*; D009504:Neutrophils / Q000473:pathology*; D014409:Tumor Necrosis Factor-alpha / Q000134:cerebrospinal fluid* / Q000502:physiology*
chemical_list: D014409:Tumor Necrosis Factor-alpha