A three-dimensional magnetically driven microrobot can carry and deliver cells to targeted areas in vivo.

A hybrid technique that combines the gravitational-sedimentation-based simple prefocusing and dielectrophoresis-based flexible separation.

Cell fusion is a fast and highly efficient technique for cells to acquire new properties. The fusion of somatic cells with stem cells can reprogram somatic cells to a pluripotent state. Our research on the fusion of stem cells and cancer cells demonstrates that the fused cells can exhibit stemness and cancer cell-like characteristics. Thus, tumor-initiating cell-like cells are generated. We employed laser-induced single-cell fusion technique to fuse the hepatocellular carcinoma cells and human embryonic stem cells (hESC). Real-time RT-PCR, flow cytometry and in vivo tumorigenicity assay were adopted to identify the gene expression difference. We successfully produced a fused cell line that coalesces the gene expression information of hepatocellular carcinoma cells and stem cells. Experimental results showed that the fused cells expressed cancer and stemness markers as well as exhibited increased resistance to drug treatment and enhanced tumorigenesis. Fusion with stem cells transforms liver cancer cells into tumor initiating-like cells. Results indicate that fusion between cancer cell and stem cell may generate tumor initiating-like cells.

Automated microinjection systems for suspension cells have been studied for years. Nevertheless, microinjection systems for adherent cells still suffer from laborious manual operations and low productivity. This paper presents a new automated microinjection system with high productivity for adherent cells. This system enhances productivity through four approaches. First, cells are detected automatically to replace manual selections. Second, the injection paths of detected cells are optimized rapidly to save time. Third, the penetration depth is adjusted adaptively according to the moving plane of the dish holder plate. Finally, constant outflow-based injection is adopted to minimize clogging. The first three approaches aim to improve the injection speed, and the last one aims to extend the usage time of micropipettes. Experiments of massive injections on MC3T3-E1 cells are performed to evaluate cell detection efficiency, injection speed, success rate, and survival rate. Results confirm that the system allows injections of over 1500 cells in one hour without much training and preparation a priori.

Optical cell manipulation has become increasingly valuable in cell-based assays. In this paper, we demonstrate the translational and rotational manipulation of filamentous cells using multiple cooperative microrobots automatically driven by holographic optical tweezers. The photodamage of the cells due to direct irradiation of the laser beam can be effectively avoided. The proposed method will enable fruitful biomedical applications where precise cell manipulation and less photodamage are required.