Cell separation using electric fields

A system for selectively inactivating biological cells based on a difference in a characteristic electroporation threshold, the system including:

• a generating mechanism which generates an electric signal constructed and arranged to create desired electric field conditions;
• a treatment cell electrically connected to said generating mechanism, said treatment cell including at least one electrode, and a treatment volume adapted to contain a cell suspension, said electrode being in fluid contact with said cell suspension during operation and being constructed of a porous biocompatible material which is sealed in order to reduce release of gases therefrom during operation.

A cell suspension comprising:

• a plurality of biological cells suspended in a liquid, each of said biological cells enclosed by a plasma membrane, where at least 90% of the biological cells that possess a maximum characteristic size in excess of a predetermined value, which comprise a subpopulation in said plurality of biological cells, have a maximum transmembrane electrical potential exceeding that required to cause irreversible dielectric breakdown of their plasma membrane.

A cell suspension comprising:

• a plurality of non-cultured biological cells suspended in a liquid, including a first plurality of viable stem cells having a characteristic size of a first value;
• said cell suspension further including a second plurality of irreversibly porated cells, essentially all of which cells have a characteristic size greater than said first value.

A method for porating cells comprising:

• supplying a suspension of cells in a treatment volume, said treatment volume including at least two electrodes in fluid contact with said suspension;
• and
• applying a time varying bipolar electrical potential across said electrodes, said potential creating an electric field sufficient to porate at least one cell in said suspension and varied so that the average current across the sample over the entire treatment time is essentially zero.

A method for reversibly porating stem cells comprising:

• supplying a suspension of cells including a plurality of stem cells having a characteristic size, a characteristic shape, a plasma membrane, and a nuclear membrane in a treatment volume;
• and
• applying a pulsed electric field to said suspension, said field having a pulse duration and magnitude sufficient to porate a plasma membrane of a cell having a characteristic size and shape essentially identical to said stem cells but having an effective membrane thickness substantially exceeding the average membrane thickness of the plasma membrane of said stem cells.

A cell suspension including a plurality of viable, reversibly electroporated stem cells.

A suspension comprising viable, human pluripotent lympho-hematopoietic stem cells, which are capable of differentiating into members of the lymphoid, erythroid, and myeloid lineages, that is essentially free of mature and lineage committed cells, said suspension being derived from a precursor cell suspension comprising substantially viable cells by subjecting said precursor suspension to an electric field of sufficient duration and magnitude to inactivate a substantial fraction of the mature and lineage committed cells in the precursor suspension.

A method for forming a plurality of essentially monodispersed cells from at least one clump of aggregated cells by:

• subjecting said at least one clump of aggregated cells to an electric field of a magnitude and duration sufficient to disaggregate said at least one clump to form a plurality of essentially monodispersed cells therefrom.