报告题目：Exosomes from M1 macrophages enhance anti-tumor
vaccine effect by regulating immune response
报告人：程丽芳 副教授（苏大药学院药剂学系）
报告时间：2015年 7月10日（星期五）10：00 AM
报告地点：独墅湖校区二期云轩楼2301室
Abstract
Immunotherapy has shown the potential to become an essential treatment of various malignancies, such as melanoma. To induce a potent MHC I restricted cytotoxic T-lymphocyte (CTL) response, cytosol delivery of an exogenous antigen into dendritic cells (DCs) is preferred. Lipid–calcium–phosphate (LCP) nanoparticles represent a new class of intracellular delivery systems for impermeable drugs.
The LCP NPs were used as a peptide vaccine delivery system for cancer therapy. To increase the encapsulation of Trp2 peptide into the calcium phosphate precipitate core of LCP, two phosphor-serine residues were added to the N-terminal of the peptide (p-Trp2). The NPs were further modified with mannose, as a target to DCs, to enhance and prolong the cargo deposit into the lymph nodes (LNs). To further enhance the anti-tumor effect of the vaccine, exosomes (Exoes), a kind of extracellular vesicles secreted from M1 polarized macrophages, were extracted and applied to regulate the in vivo immune response. Both vaccine NPs and Exoes can be accumulated into LNs. Through in vitro and in vivo study showed that M1 Exoes did improve the anti-tumor efficacy by stimulating various cytokines of Th1 response to regulate the immune response, and the mechanism was studied and discussed.
Thus, encapsulation of phospho-peptide antigens into LCP may be a promising strategy for antigen delivery in cancer immunotherapy, and Exoes from M1 macrophages could be an efficient adjuvant for enhancing the anti-tumor immune response of vaccines.
