title: Gamma delta T lymphocytes and proinflammatory cytokines in bacterial meningitis.
abstract: BACKGROUND
  Patients with bacterial meningitis have a T-cell defect and impaired cytokine production.
  
  
  METHODS
  The phenotype and percentage of circulating alpha beta and gamma delta T-cell receptor-bearing lymphocytes were determined from patients with bacterial meningitis (Haemophilus influenzae, Streptococcus pneumoniae, and Neisseria meningitidis), patients with bacterial infection but without meningitis, and healthy control subjects by a monoclonal antibody staining method. The in vitro production of cytokines, interleukins (IL-2, IL-6), interferon-gamma and tumor necrosis factor-alpha was measured by the bioassay or ELISAs.
  
  
  RESULTS
  The percentage of circulating gamma delta T cells with a CD3+CD4+CD8- phenotype was significantly (p < 0.001) increased in all patients with bacterial meningitis compared with patients with bacterial infection and healthy control subjects. The CD3+ gamma delta T cells from patients with meningitis produced highly elevated levels of two proinflammatory cytokines, tumor necrosis factor-alpha and IL-6. However, interferon-gamma production was enhanced by CD3+ alpha beta T cells.
  
  
  CONCLUSIONS
  The increased percentage of circulating T-cell receptor gamma delta T cells and their in vitro production of tumor necrosis factor-alpha and IL-6 cytokines may play an important role in the pathogenesis and inflammatory response in bacterial meningitis.
authors.affiliation: Department of Clinical Immunology, King Saud University, College of Medicine, Abha, Saudi Arabia.
authors.forename: S
authors.initials: S
authors.lastname: Raziuddin
authors.forename: N A
authors.initials: NA
authors.lastname: Mir
authors.lastname: el-Awad M el-H
authors.forename: A W
authors.initials: AW
authors.lastname: Telmesani
authors.forename: M
authors.initials: M
authors.lastname: al-Janadi
mesh_terms: D000911:Antibodies, Monoclonal; D001419:Bacteria / Q000276:immunology; D001424:Bacterial Infections / Q000276:immunology; D017252:CD3 Complex / Q000276:immunology; D002675:Child, Preschool; D004731:Endotoxins / Q000097:blood; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D016130:Immunophenotyping; D015850:Interleukin-6 / Q000096:biosynthesis*; D008297:Male; D016920:Meningitis, Bacterial / Q000276:immunology*; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000276:immunology; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis*
chemical_list: D000911:Antibodies, Monoclonal; D017252:CD3 Complex; D004731:Endotoxins; D015850:Interleukin-6; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016692:Receptors, Antigen, T-Cell, gamma-delta; D014409:Tumor Necrosis Factor-alpha