1. Cell-mediated lysis of autologous platelets in chronic idiopathic thrombocytopenic purpura
- Author
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Ming Hou, Lizhen Li, Lin Wang, Xiaoxia Chu, Yuan-yuan Zhu, Jun Peng, Feng Zhang, and Daoxin Ma
- Subjects
Adult ,Blood Platelets ,Cytotoxicity, Immunologic ,Male ,Pore Forming Cytotoxic Proteins ,Fas Ligand Protein ,Adolescent ,chemical and pharmacologic phenomena ,CD8-Positive T-Lymphocytes ,Autoantigens ,Granzymes ,Fas ligand ,TNF-Related Apoptosis-Inducing Ligand ,immune system diseases ,hemic and lymphatic diseases ,medicine ,Humans ,Cytotoxic T cell ,RNA, Messenger ,Purpura, Thrombocytopenic, Idiopathic ,Membrane Glycoproteins ,biology ,Perforin ,Tumor Necrosis Factor-alpha ,Chemistry ,Serine Endopeptidases ,hemic and immune systems ,Hematology ,General Medicine ,Middle Aged ,Flow Cytometry ,medicine.disease ,Thrombocytopenic purpura ,Killer Cells, Natural ,Granzyme B ,Granzyme ,Chronic Disease ,Tumor Necrosis Factors ,Immunology ,biology.protein ,Female ,Tumor necrosis factor alpha ,Apoptosis Regulatory Proteins ,CD8 ,T-Lymphocytes, Cytotoxic - Abstract
Objectives: Investigate the contribution and mechanism of cell-mediated cytotoxicity to the pathogenesis of idiopathic thrombocytopenic purpura (ITP). Methods: We observed the cytotoxic effect of cytotoxic T-lymphocyte (CTL) (CD8 + ) and natural killer cells (CD3 - CD16 + CD56 + ) toward chronic ITP patient's autologous platelets, and investigated the expression of Fas ligand (FasL), tumor necrosis factor (TNF)-a and TNF-related apoptosis inducing ligand, as well as perforin and granzyme B mRNA in CD8 + cells using flow cytometry and reverse transcriptase-polymerase chain reaction. Results: We found that platelet lysis was seen only using purified CD8 + T cells as effector cells; expression of FasL and TNF-α in CD8 + T cells in ITP group was elevated. Moreover, the mRNA levels of granzyme B and perforin in CD8 + cells of ITP patients were increased. Conclusions: Our findings suggest that CTLs are activated in chronic ITP and might be involved in the pathogenesis of this disorder. Apoptosis and perforin/granzyme-mediated cytotoxicity constitute an important pathway through which CTLs destruct autologous platelets. CTLs might be a reasonable target for a therapeutic strategy.
- Published
- 2006
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