Abstract: Aspects of the disclosure are directed to a technique for sequential electroporation that provides for a delivery of multiple electrical pulses separated in time to cells, cell particles, lipid vesicles, liposomes, or to increase efficiency of entry of one or more agents of interest into cells, cell particles, lipid vesicles, liposomes, tissues, or derivatives thereof, and to minimize damage by electrical arc or heat shock; increase loading efficiency of an agent of interest; and maintain viability of the cells, cell particles, lipid vesicles, or tissues and the ability of the cells, cell particles, lipid vesicles, liposomes, or tissues to produce a clinical effect.

Abstract: Compositions and methods concern the sequence modification of an endogenous genomic DNA region. Certain aspects relate to a method for site-specific sequence modification of a target genomic DNA region in cells comprising: contacting the cells with an activating composition; transfecting the cells with a transfection composition comprising (a) donor DNA and (b) a DNA digesting agent; wherein the donor DNA comprises: (i) a homologous region comprising nucleic acid sequence homologous to the target genomic DNA region; and (ii) a sequence modification region; and wherein the genomic DNA sequence is modified specifically at the target genomic DNA region.

Abstract: The present invention relates to the transient modification of cells. In particular embodiments, the cells are immune systems, such as PBMC, PBL, T (CD3+ and/or CD8+) and Natural Killer (NK) cells. The modified cells provide a population of cells that express a genetically engineered chimeric receptor which can be administered to a patient therapeutically. The present invention further relates to methods that deliver mRNA coding for the chimeric receptor to unstimulated resting PBMC, PBL, T (CD3+ and/or CD8+) and NK cells and which delivers the mRNA efficiently to the transfected cells and promotes significant target cell killing.

Abstract: Compositions and methods for reducing nucleotide oxidation during electroporation, specifically the use of free radical scavengers to reduce electroporation-induced oxidation, are described. Compositions and methods for enhancing transfection efficiency are also described.