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1.
Braz. j. med. biol. res ; 48(12): 1095-1100, Dec. 2015. graf
Article in English | LILACS | ID: lil-762920

ABSTRACT

In DNA vaccines, the gene of interest is cloned into a bacterial plasmid that is engineered to induce protein production for long periods in eukaryotic cells. Previous research has shown that the intramuscular immunization of BALB/c mice with a naked plasmid DNA fragment encoding the Mycobacterium leprae 65-kDa heat-shock protein (pcDNA3-Hsp65) induces protection against M. tuberculosis challenge. A key stage in the protective immune response after immunization is the generation of memory T cells. Previously, we have shown that B cells capture plasmid DNA-Hsp65 and thereby modulate the formation of CD8+ memory T cells after M. tuberculosis challenge in mice. Therefore, clarifying how B cells act as part of the protective immune response after DNA immunization is important for the development of more-effective vaccines. The aim of this study was to investigate the mechanisms by which B cells modulate memory T cells after DNA-Hsp65 immunization. C57BL/6 and BKO mice were injected three times, at 15-day intervals, with 100 µg naked pcDNA-Hsp65 per mouse. Thirty days after immunization, the percentages of effector memory T (TEM) cells (CD4+ and CD8+/CD44high/CD62Llow) and memory CD8+ T cells (CD8+/CD44high/CD62Llow/CD127+) were measured with flow cytometry. Interferon γ, interleukin 12 (IL-12), and IL-10 mRNAs were also quantified in whole spleen cells and purified B cells (CD43−) with real-time qPCR. Our data suggest that a B-cell subpopulation expressing IL-10 downregulated proinflammatory cytokine expression in the spleen, increasing the survival of CD4+ TEM cells and CD8+ TEM/CD127+ cells.


Subject(s)
Animals , Male , Mice , B-Lymphocytes/immunology , Heat-Shock Proteins/immunology , Immunomodulation/genetics , /genetics , RNA, Messenger/immunology , T-Lymphocyte Subsets/immunology , B-Lymphocytes/metabolism , Flow Cytometry , Gene Expression/genetics , Heat-Shock Proteins/therapeutic use , Immunologic Memory/physiology , Immunophenotyping/classification , Inflammation Mediators/analysis , Interferon-gamma/analysis , /immunology , /analysis , Mice, Knockout , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , RNA, Messenger/genetics , Spleen/cytology , Spleen/immunology , T-Lymphocyte Subsets/classification , Vaccines, DNA/immunology , Vaccines, DNA/therapeutic use
2.
Mem. Inst. Oswaldo Cruz ; 96(suppl): 89-101, Sept. 2001. ilus, graf, tab
Article in English | LILACS | ID: lil-295895

ABSTRACT

T cell clones were derived from peripheral blood mononuclear cells of Schistosoma haematobium infected and uninfected individuals living in an endemic area. The clones were stimulated with S. haematobium worm and egg antigens and purified protein derivative. Attempts were made to classify the T cell clones according to production of the cytokines IL-4, IL-5 and IFN-gamma. All the T cell clones derived were observed to produce cytokines used as markers for the classification of Th1/Th2 subsets. However, the 'signature' cytokines marking each subset were produced at different levels. The classification depended on the dominating cytokine type, which was having either Th0/1 or Th0/2 subsets. The results indicated that no distinct cytokine profiles for polarisation of Th1/Th2 subsets were detected in these S. haematobium infected humans. The balance in the profiles of cytokines marking each subset were related to infection and re-infection status after treatment with praziquantel. In the present study, as judged by the changes in infection status with time, the T cell responses appeared to be less stable and more dynamic, suggesting that small quantitative changes in the balance of the cytokines response could result in either susceptibility or resistant to S. haematobium infection


Subject(s)
Humans , Animals , Child , Cytokines/biosynthesis , Schistosoma haematobium/immunology , Schistosomiasis haematobia/immunology , T-Lymphocytes, Helper-Inducer/classification , Anthelmintics/therapeutic use , Antigens, Helminth , Cell Line , Clone Cells/classification , Clone Cells/metabolism , Cytokines/analysis , Cytokines/isolation & purification , Enzyme-Linked Immunosorbent Assay , Follow-Up Studies , Parasite Egg Count , Praziquantel/therapeutic use , Schistosomiasis haematobia/drug therapy , T-Lymphocyte Subsets/classification , T-Lymphocyte Subsets/metabolism , T-Lymphocytes, Helper-Inducer/metabolism , Th1 Cells/classification , Th1 Cells/metabolism , Th2 Cells/classification , Th2 Cells/metabolism , Titrimetry
3.
Indian J Pathol Microbiol ; 1996 Jan; 39(1): 13-7
Article in English | IMSEAR | ID: sea-74771

ABSTRACT

The blast cell populations of 25 patients of chronic myeloid leukemia in blast crisis (CML-BC) were studied for morphological, cytochemical and immunophenotypic features. The patients were divided into 6 broad groups based upon the pattern of surface marker positivity-myeloblastic, mixed myeloblastic, megakaryoblastic, mixed lineage, lymphoid and undifferentiated blast crisis. Myeloperoxidase (MPO), Sudan Black B (SBB) and Chloroacetate esterase (CAE) stains showed 100% specificity for the myelomonocytic lineage but the sensitivity was low. Periodic acid Schiff (PAS) stain was neither specific nor sensitive for the lymphoid lineage. Immunophenotyping as compared to morphologic and cytochemical assessment, was seen to be most useful for assigning a lineage to leukemic cells in CML-BC.


Subject(s)
Adult , Blast Crisis/pathology , Female , Humans , Immunophenotyping , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology , Male , Middle Aged , Phenotype , T-Lymphocyte Subsets/classification
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