Document 0532
 DOCN  M9550532
 TI    Acanthamoeba-specific human T-cell clones isolated from healthy
       individuals.
 DT    9505
 AU    Tanaka Y; Suguri S; Harada M; Hayabara T; Suzumori K; Ohta N; Department
       of Parasitology, Okayama University Medical School,; Japan.
 SO    Parasitol Res. 1994;80(7):549-53. Unique Identifier : AIDSLINE
       MED/95158365
 AB    T-cell responses to pathogenic free-living amoebae, Acanthamoeba sp.,
       were analyzed in healthy Japanese individuals. Of 20 healthy subjects,
       10 (50%) showed significant proliferative responses of peripheral blood
       mononuclear cells to the soluble amoebic antigens in vitro. The antigens
       used were not mitogenic, and no evidence of amoebic superantigens was
       available. We established human T-cell clones reactive to Acanthamoeba,
       all of which were CD3- and CD4-positive, CD8-negative, and TCR-alpha
       beta-positive. We isolated two strains of Acanthamoeba from two
       patients, one from a patient with meningoencephalitis (CSF strain) and
       the other from a patient with keratitis (K strain). Of 13 clones, 11
       were reactive to the K-strain as well as to the CSF-strain antigen under
       human leukocyte antigen (HLA)-DR restriction, whereas the other two were
       specific for the K-strain antigen. All but one clone tested showed
       TH1-equivalent functions because these cells produced interferon
       (IFN)-gamma in response to the amoebic antigen but produced no
       detectable level of interleukin 4 (IL-4). These results suggest that
       immunocompetent hosts might have acquired protective immunity mediated
       by Acanthamoeba-specific T-cells during natural sensitization.
 DE    Acanthamoeba/*IMMUNOLOGY/PATHOGENICITY  Adult  Animal  Antigens,
       Protozoan/*IMMUNOLOGY  Clone Cells  Female  Human  HLA-DR
       Antigens/IMMUNOLOGY  Immunity, Cellular  Infant, Newborn  Interferon
       Type II/BIOSYNTHESIS  Interleukin-4/BIOSYNTHESIS  Japan  Lymphocyte
       Transformation  Male  Mice  Mice, Inbred BALB C  Middle Age  Support,
       Non-U.S. Gov't  Support, U.S. Gov't, Non-P.H.S.
       T-Lymphocytes/*IMMUNOLOGY  Th1 Cells/IMMUNOLOGY  Virulence  JOURNAL
       ARTICLE

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