In situ poly I:C released from living cell drug nanocarriers for macrophage-mediated antitumor immunotherapy.

Immunotherapy is one of the most promising approaches to inhibit tumor growth and metastasis by activating host immune functions. However, the arising problems such as low immune response caused by complex tumor microenvironment and extremely systemic immune storm still limit the clinical applications of immunotherapy. Here, we construct Poly I: C-encapsulated poly (lactic-co-glycolic acid) nanoparticles (PLP NPs) with a slow release profile. A biomimetic system (MPLP), which loads PLP NPs on the surface of bone marrow-derived macrophage (BMDM) via the maleimide-thiol conjugation, is synthesized to effectively deliver PLP, control drug release and activate the tumor-specific immune response in situ. The results show that PLP NPs loading does not affect the activity and function of BMDM. Then, BMDM acts as a living cell drug vehicle and promotes the accumulation of PLP NPs in tumors, where Poly I: C is released from PLP NPs and reprograms BMDM into tumoricidal M1 macrophage. Furthermore, MPLP triggers potent antitumor immune responses in vivo and effectively inhibits local and metastatic tumors without causing adverse pathological immune reactions. This study offers an inspiration to facilitate clinical translation through the delivery of drugs by living immune cells for future anticancer therapy.

A micro gas chromatographic column with embedded elliptic cylindrical posts.

In this paper, a novel embeded elliptic cylindrical posts (ECPs) with large surface area and wide effective width, which could support more stationary phase and decrease the pressure drop, is applied on the micro-fabricated gas chromatographic (µGC) column. Compared with µGC column with cylindrical posts (CPs), the surface area and effective width of µGC column with ECPs are increased by 29% and 30%. Separation experiments are performed under the same head pressure at column inlet: in experiments of separating mixture 1, the column efficiency of the µGC column with ECPs for C9 has a 76% improvement, and the separation resolution between C8 and C9 also has a 34% improvement; in experiments of separating mixture 2, seven kinds of analytes can be identified by the µGC column with ECPs less than ten minutes, while, only six kinds can be identified by the µGC column with CPs in almost the same time. In detail, the column efficiency of the µGC column with ECPs for toluene has a 129% improvement, and the separation resolution between benzene and toluene also has a 56.4% improvement. Hence, the µGC column with the inner structures of ECPs is a valid means to improve column efficiency and resolution in a lower pressure drop.