〔Abstract〕 Objective To investigate the effects of exosomes derived from Hepa1-6 cellson dendritic maturation and function. Methods Exosomes were extracted from Hepa1-6 cells, and the shape of exosomes was identified by transmission electron microscopy. The expressions of the marker proteins of exosomes, CD63 and TSG101 were determined by Western-blot.Dendritic cellswere impacted with exosomes from Hepa1-6 cells, and the expression of maturation related surface molecules CD40, CD80, CD83, CD86 and MHC-Ⅱ was detected by flow cytometry.Mouse T lymphocytes and exosomes shock DCs from Hepa1-6 cells were co-incubated for 5 d, and the proliferation of T lymphocytes was determined by CFSE staining and flow cytometry. Results The exosomes collected from thesupernatantof Hepa1-6 cells was observed by transmission electron microscopy and exosomesshowed round or circular membranous vesicle-like structure, which was consistent with the typical characteristics of exosomes.Western-blot analysis showed that exosomesderived from Hepa1-6 cells expressed CD63 and TSG101, but did not express Cytochrome C.The exosomes extracted from Hepa1-6 cells were used to shock DCs, and the surface MHC-II molecules, mature marker CD83 and co-stimulating molecules CD40, CD80 and CD86 were up-regulated.Moreover, with the increase of exosomes concentration, the molecular expression of DC surface increased(P<0.05). Exosomes also promoted the proliferation of T lymphocytes(P<0.05). Conclusion Exosomes extracted from Hepa1-6 cells could promote the differentiation of DC2.4 toward mature phenotype and promote the proliferation of T cells.