Chronic myeloid leukemia (CML) is a malignant proliferative disorder of pluripotential hemopoietic stem cell. A lot of clinical and laboratory evidences proved that CML cells have immunogenicity. It would be susceptible target for cell-mediated immunity against leukemia cells. There is no ideal cure method at present. The use of adoptive immunotherapy involving expanded anti-leukemia cytotoxic T cells may offer a reasonable approach to eliminate residual disease in these patients. The biology of small vesicles secreted from tumor cells recently raised a great deal of interest with the demonstration of their potent immunostimulatory functions in tumor models.In the first part of our experiments, exosome derived from 5 CML patients and K562 cells were purified by ultrafiltration centrifugation and sucrose gradient ultracentrifugation. Electron microscopy was used to observe their ultrastructures. The expression of HSP70, ICAM-1, ABL were investigated by solid phase immunoelectron microscopic method (SPIEM). Transmission electron microscopy reavealed that the vesicles of these preparations were of the size (50 nm~100 nm in diameter) and morphology (round or ellipse)...
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