title: Bacterial meningitis: T cell activation and immunoregulatory CD4+ T cell subset alteration.
abstract: Meningitis is the most important cause of acquired postnatal deafness and neurologic disorders in children. To determine if cell-mediated immunity is casually related to the pathogenesis of bacterial meningitis, T cell subsets were quantitated from blood of the 29 children with clinical and bacteriologic diagnosis of Haemophilus influenzae, Streptococcus pneumoniae, and Neisseria meningitidis bacterial meningitis. The CD4+ T cells increased and CD8+ T cells decreased in patients with meningitis as compared to patient control subjects (bacterial infections without meningitis) and normal healthy control subjects. An elevated percentage of CD25+ (interleukin-2 receptors) and HLA-DR+ (immune-response gene-associated antigen) T cells were detected from all patients with meningitis. All 29 patients with meningitis had highly elevated CD4+ CD45R+ (suppressor-inducer) cells and reciprocally depressed CD4+ CDw29+ (helper-inducer) cells compared with healthy age-matched normal and patient control subjects. These findings indicate characteristic immunologic T cell abnormalities from meningitis. The abnormal increase in the CD4+ CD45R+ suppressor-inducer or "virgin" cells and expression of activation antigens on T cells may be of help in future understanding of abnormal immune reactions from bacterial meningitis. However, deficiency of the CD4+ CDw29+ helper-inducer or "memory" cells may contribute to the impaired helper function for B cell-induced protective antibody synthesis to bacterial capsular polysaccharides found in this disease.
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: M E
authors.initials: ME
authors.lastname: el-Awad
authors.forename: N A
authors.initials: NA
authors.lastname: Mir
mesh_terms: D015703:Antigens, CD / Q000032:analysis; D000943:Antigens, Differentiation / Q000032:analysis; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis; D001424:Bacterial Infections / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D016827:CD8 Antigens; D002675:Child, Preschool; D005260:Female; D006684:HLA-DR Antigens / Q000032:analysis; D006649:Histocompatibility Antigens / Q000032:analysis; D006801:Humans; D019012:Integrin beta1; D017493:Leukocyte Common Antigens; D007958:Leukocyte Count; D008213:Lymphocyte Activation; D008297:Male; D008581:Meningitis / Q000276:immunology*; D015375:Receptors, Interleukin-2 / Q000032:analysis; D016176:T-Lymphocyte Subsets / Q000276:immunology*
chemical_list: D015703:Antigens, CD; D000943:Antigens, Differentiation; D000945:Antigens, Differentiation, T-Lymphocyte; D016827:CD8 Antigens; D006684:HLA-DR Antigens; D006649:Histocompatibility Antigens; D019012:Integrin beta1; D015375:Receptors, Interleukin-2; D017493:Leukocyte Common Antigens