5 results about "Transfection" patented technology

The invention relates to a method for manufacturing a recombinant polyclonal protein composition, in particular a recombinant polyclonal antibody composition. The method comprises obtaining a collection of cells transfected with a library of variant nucleic acid sequences, wherein each cell in the collection is transfected with and capable of expressing one member of the library, which encodes a distinct member of a polyclonal protein that binds a particular antigen and which is located at the same single site in the genome of individual cells in said collection, wherein said nucleic acid sequence is not naturally associated with said cell in the collection. The cells are cultured under suitable conditions for expression of the polyclonal protein, which is obtained from the cells or culture supernatant. The nucleic acid sequence id introduced into the cells by transfection with a library of vectors for site-specific integration. The present method is suitable for manufacturing recombinant polyclonal antibodies, thereby mailing available a superior replacement of plasma-derived therapeutic immunoglobulin products.

This invention provides a method for accelerating the proliferation of human mesenchymal stem cells, which comprises the steps of: transfecting recombinant expression carrier containing EGF to human mesenchymal stem cells, and stimulating with a certain concentration of calcium ions during the transfection process to divide into typical stem cells. Under nude mouse subcutaneous microenvironment induction, the stem cells are further divided into skin tissue stem cells, thus directly taking part in the proliferation of nude mouse hair. This invention can obtain rapidly proliferated human mesenchymal stem cells, thus having a potential application in clinical skin wound treatment.

Problems with transience of siRNA-mediated knock-down and transfection efficiency have limited the scope of RNAi-based experiments. The invention provides a tool for employing RNAi more efficiently and effectively by integrating RNAi expression with methods of cell enrichment.

The invention discloses a cell tracer with low toxicity and a high cell uptake rate as well as a preparation method and application of the cell tracer. The cell tracer is a PAA and PEG coated ultra-small superparamagnetic iron oxide nanoparticle. The cell tracer is obtained by synthesizing an ultra-small superparamagnetic iron oxide nanoparticle through a thermal decomposition method and then sequentially coating PAA and PEG. The cell tracer with the low toxicity and the high cell uptake rate is obtained by coating the ultra-small superparamagnetic iron oxide nanoparticles with the PAA and thePEG, and can be used as a cell tracer applied to nuclear magnetic resonance imaging; the cell tracer can be used for efficiently marking human adipose tissue-derived stromal cells without using a transfection reagent, has no obvious toxicity to the human adipose tissue-derived stromal cells and induced pluripotent stem cells, and can be used for tracing the human umbilical cord mesenchymal stem cells transplanted into a brain of a rat.