Objective To investigate the stimulation of exosome derived from osteosarcoma cells suppressing cytotoxic T cells and the inhibitory effect of active T cells for surpressing osteosarcoma cells. Methods Exosome derived from tumor cells was isolated and purified by ultracentrifugation. Its morphology was observed with transmission electron microscope, and the major histocompatibility complex-I ( MHC-I) molecules were analyzed by western blot. Mice bone marrow-derived dendritic cells were pulsed with exosome. Surface membrane MHC-I molecules were analyzed with flow cytometry. The effect of active T cells on the growth of osteosarcoma cells were detected by MTT assay after the T cells being stimulated by exosome-pulsed dendritic cells. Results The exosome was round or near round corpuscle, and the diameter was about 50-100 nm by transmission electron microscope. The size was relatively homogeneous. Western blot showed that the exosome expressed MHC-Ⅰmolecules. Surface membrane CD80,MHC-I and II molecules were expressed on 77. 16%, 83. 21%, and 91. 26% of LPS-treated dendritic cells, respectively, which were up-regulated compared to untreated cells. Dendritic cells pulsed with exosome derived from osteosarcoma cells caused significantly higher T cells stimulation and osteosarcoma cells inhibition as compared to un-pulsed dendritic cells. (P<0.05). Conclusion T cells can inhibit the growth of osteosarcoma cells after being stimulated by exosome-pulsed dendritic cells in vitro.

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OBJECTIVETo research the effects of moschus, borneol, styrax and benzoinum on the structure and function of blood brain barrier in cerebral ischemia-reperfusion injury model rats.

METHODFocal middle cerebral artery occlusion (MCAO) was introduced as an in vivo ischemic model in rats. After 2 h MCAO, nylon suture was pulled up 1 cm to give blood reperfusion. After 22 h reperfusion, all animals were decapitated. The ultramicrostructure of blood brain barrier of ischemia hemisphere side in fronto-parietal cortex region by transmission electron microscope, and the content of VEGF and MMP-9 in ischemia side brain tissue were measured by ELISA.

RESULTIn model and solvent group rats, the capillary endothelium cells, astro-glial cells and nerve cells in ischemia hemisphere side in fronto-parietal region were emerged in different degree compared with sham-operated groups, which exhibited tight junction between endothelial cells being opened, basal lamina being dissolved, and permeability increasing, and cellularedema. In borneol (0.2 g x kg(-1)) group rats, the structure of three kinds of cells were nearly normal, which tight junction structure was clear, rough endoplasmic reticulum and polyribosome could be found in cytoplasm. In moschus (66.6 mg x kg(-1)) group rats, the structure of capillary endothelium cells and astrocytes were nearly normal as well as the basal lamina, but the electrons in neurons was maldistribution. In styrax (1.332 g x kg(-1)) group rats, astrocytes were nearly normal, while capillary endothelial cells and neurons exhibited oedema in different degrees. And the basal lamina was discontinuous, augmentation of cell spaces in endothelial cells increased the permeability, some endoplasmic reticulum broadened and ribosome ablated. In benzoinum (1.0 g x kg(-1)) group rats, oedema of capillary endothelial cells and astrocytes was significant, basal lamina broke. Meanwhile endoplasmic reticulum broadened as vacuole, the number of ribosome in rough endoplasmic reticulum decreased, crista mitochondriales in some neurons disappeared as vacuole which hint oedema happened. Results also showed that borneol decrease the level of VEGF in ischemia side brain tissue significantly, while has little influence on the level of MMP-9. Moschus showed the tendency to decrease the level of VEGF and MMP-9 in ischemia side brain tissue.

CONCLUSIONAromatic resuscitation drugs showed the protection effect on blood brain barrier in cerebral ischemia-reperfusion injury rats, which the protection effect of moschus and borneol were better than that of styrax and benzoinum. The mechanism of protection effect maybe related to decrease the level of VEGF and MMP-9.

Animals ; Benzoin ; pharmacology ; Blood-Brain Barrier ; drug effects ; metabolism ; ultrastructure ; Bornanes ; pharmacology ; Brain Ischemia ; drug therapy ; metabolism ; Disease Models, Animal ; Fatty Acids, Monounsaturated ; pharmacology ; Infarction, Middle Cerebral Artery ; drug therapy ; metabolism ; Male ; Matrix Metalloproteinase 9 ; drug effects ; metabolism ; Neuroprotective Agents ; pharmacology ; Plant Extracts ; pharmacology ; Rats ; Reperfusion Injury ; drug therapy ; metabolism ; Styrax ; chemistry ; Vascular Endothelial Growth Factor A ; drug effects ; metabolism