       Document 1015
 DOCN  M9621015
 TI    T cell blastogenic responses to Toxoplasma gondii trophozoites among
       HIV-infected patients.
 DT    9602
 AU    Carrega G; Canessa A; Argenta P; Cruciani M; Bassetti D; Department of
       Infectious Diseases, University of Genoa, Italy.
 SO    AIDS Res Hum Retroviruses. 1995 Jun;11(6):741-6. Unique Identifier :
       AIDSLINE MED/96078235
 AB    OBJECTIVE: To evaluate the cell-mediated immune response to Toxoplasma
       gondii (T. gondii) among HIV-infected patients. METHODS: Forty
       HIV-infected patients were studied. Of them, 35 had antibodies to T.
       gondii and 5 had not. Nine of 35 patients with detectable serum
       Toxoplasma antibodies were classified as group A1 (CDC 1993), 10 as
       group B2, 6 as group B3, and 10 as group C3. Peripheral blood
       mononuclear cells (PBMCs) were obtained by Ficoll-Hypaque gradient
       centrifugation. Living Toxoplasma gondii trophozoites, herpes simplex
       virus (HSV), tetanus toxoid, and phytohemoagglutinin (PHA) were used in
       standard proliferation assays. Toxoplasma-responding blasts were
       expanded and assayed for antigen specificity and HLA restriction by
       proliferation assays. T cell subsets were analyzed using two-color flow
       cytometry. RESULTS: Among patients with detectable Toxoplasma serum
       antibodies, significant PBMC proliferation in response to T. gondii
       trophozoites was observed in those classified in group A1 or B2 but not
       in those in groups B3 and C3. Toxoplasma-induced blasts from five of six
       patients after 7 days of culture and from five patients after 15 days of
       culture proliferated in response to T. gondii in the presence of either
       autologous or allogeneic PBMCs as antigen-presenting cells (APCs) and/or
       also proliferated in response to HSV. The surface markers of T.
       gondii-induced blasts showed a variable percentage of CD4 and CD8
       activated cells. CONCLUSIONS: T cell proliferative response to living
       trophozoites of T. gondii is lost only in patients with severe depletion
       of CD4 cells. PBMC proliferation was observed only in patients with
       previous T. gondii infection, but the T cell blasts generated showed a
       strong alloreactivity (proliferating in response to allogeneic
       irradiated PBMCs) and were apparently not antigen specific
       (proliferating also in response to HSV).
 DE    Adult  Animal  Antibodies, Protozoan/BLOOD  Antigen-Presenting
       Cells/IMMUNOLOGY  Antigens, CD/ANALYSIS  CD4-CD8 Ratio  CD4-Positive
       T-Lymphocytes/*IMMUNOLOGY  CD8-Positive T-Lymphocytes/*IMMUNOLOGY
       Female  Human  HIV Infections/*IMMUNOLOGY  Leukocytes,
       Mononuclear/IMMUNOLOGY  *Lymphocyte Transformation/DRUG EFFECTS  Male
       Middle Age  Phytohemagglutinins/PHARMACOLOGY  Simplexvirus/IMMUNOLOGY
       Support, Non-U.S. Gov't  T-Lymphocyte Subsets  Tetanus
       Toxoid/PHARMACOLOGY  Toxoplasma/*IMMUNOLOGY  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).

