Geron Corporation

Other

Asterias Biotherapeutics, Inc.

Roslin Institute (edinburgh)

Joseph D Gold

Chunhui Xu

Melissa K Carpenter

Ramkumar Mandalam

Margaret Inokuma

Jane S Lebkowski

Mohammad Hassanipour

Michael D West

James T Murai

Choy-Pik Chiu

Lila R Collins

Andrea G Bodnar

Walter D Funk

Ralph Brandenberger

Lawrence W Stanton

J Michael Schiff

Michael Mok

John M Irving

Jim McWhir

This disclosure provides an improved system for culturing human pluripotent stem cells. Traditionally, pluripotent stem cells are cultured on a layer of feeder cells (such as mouse embryonic fibroblasts) to prevent them from differentiating. In the system described here, the role of feeder cells is replaced by components added to the culture environment that support rapid proliferation without differentiation. Effective features are a suitable support structure for the cells, and an effective medium that can be added fresh to the culture without being preconditioned by another cell type. Culturing human embryonic stem cells in fresh medium according to this invention causes the cells to expand surprisingly rapidly, while retaining the ability to differentiate into cells representing all three embryonic germ layers. This new culture system allows for bulk proliferation of pPS cells for commercial production of important products for use in drug screening and human therapy.

Screening methods for human embryonic stem cells

The present application describes the new methods for the differentiation of primate pluripotent stem cells into cardiomyocyte-lineage cells. The methods utilize sequential culturing of the primate pluripotent stem cells in certain growth factors to produce cardiomyocyte-lineage cells. In certain embodiments of the invention, the population of cells produced by the sequential culturing is further enriched for cardiomyocyte-lineage cells so as to produce a higher percentage of those cells.

Differentiation of primate pluripotent stem cells to cardiomyocyte-lineage cells

This invention provides a system for producing differentiated cells from a stem cell population for use wherever a relatively homogenous cell population is desirable. The cells contain an effector gene under control of a transcriptional control element (such as the TERT promoter) that causes the gene to be expressed in relatively undifferentiated cells in the population. Expression of the effector gene results in depletion of undifferentiated cells, or expression of a marker that can be used to remove them later. Suitable effector sequences encode a toxin, a protein that induces apoptosis; a cell-surface antigen, or an enzyme (such as thymidine kinase) that converts a prodrug into a substance that is lethal to the cell. The differentiated cell populations produced according to this disclosure are suitable for use in tissue regeneration, and non-therapeutic applications such as drug screening.

Isolated in vitro cell population comprising primate pluripotent stem cells containing a nucleic acid construct and differentiated progeny of the pluripotent stem cells

Primate pluripotent stem cell expansion without feeder cells and in the presence of FGF and matrigel or Engelbreth-Holm-Swarm tumor cell preparation

Human embryonic stem cells genetically modified to contain a nucleic acid and cultured with fibroblast growth factor

In vitro differentiated cell and human embryonic stem cell population

Micro-carrier culture system for rapid expansion of human embryonic stem cells

This invention provides a new procedure for generating cardiomyocyte lineage cells from embryonic stem cells for use in regenerative medicine. Differentiating by way of embryoid body formation or in serum is no longer required. Instead, the stem cells are plated onto a solid substrate, and differentiated in the presence of select factors and morphogens. After enrichment for cells with the appropriate phenotype, the cells are allowed to cluster into Cardiac Bodies&#x2122;, which are remarkably homogeneous and suitable for the treatment of heart disease.

Direct differentiation method for making cardiomyocytes from human embryonic stem cells

This invention provides populations human cells of the cardiomyocyte lineage. The cells are obtained by causing cultures of pluripotent stem cells to differentiate in vitro, and then harvesting cells with certain phenotypic features. Differentiated cells bear cell surface and morphologic markers characteristic of cardiomyocytes, and a proportion of them undergo spontaneous periodic contraction. Highly enriched populations of cardiomyocytes and their replicating precursors can be obtained, suitable for use in a variety of applications, such as drug screening and therapy for cardiac disease.

Process for making transplantable cardiomyocytes from human embryonic stem cells

This invention provides a new procedure for generating cardiomyocyte lineage cells from embryonic stem cells for use in regenerative medicine. Differentiating by way of embryoid body formation or in serum is no longer required. Instead, the stem cells are plated onto a solid substrate, and differentiated in the presence of select factors and morphogens. After enrichment for cells with the appropriate phenotype, the cells are allowed to cluster into cardiac bodies&#x2122;, which are remarkably homogeneous and suitable for the treatment of heart disease.

Methods and materials for culturing primate-derived primordial stem cells are described. In one embodiment, a cell culture medium for growing primate-derived primordial stem cells in a substantially undifferentiated state is provided which includes a low osmotic pressure, low endotoxin basic medium that is effective to support the growth of primate-derived primordial stem cells. The basic medium is combined with a nutrient serum effective to support the growth of primate-derived primordial stem cells and a substrate selected from feeder cells and an extracellular matrix component derived from feeder cells. The medium further includes non-essential amino acids, an anti-oxidant, and a first growth factor selected from nucleosides and a pyruvate salt.

Feeder-free culture method for embryonic stem cells or primate primordial stem cells

This disclosure provides a system for obtaining genetically altered primate pluripotent stem (pPS) cells. The role of the feeder cells is replaced by supporting the culture on an extracellular matrix, and culturing the cells in a conditioned medium. The cells can be genetically altered with a viral vector or DNA/lipid complex, and then selected for successful transfection by drug-resistant phenotype in the transfected cells. The system allows for bulk proliferation of genetically altered pPS cells as important products for use in human therapy or drug screening.

Human embryonic stem cells having genetic modifications

Culture system for rapid expansion of human embryonic stem cells

This disclosure provides a system for qualifying embryonic stem cells intended for human therapy. A large-scale sequencing project has identified important markers that are characteristic of undifferentiated pluripotent cells. Combinations of these markers can be used to validate the self-renewing capacity of ES cells, and their ability to differentiate into tissue types suitable for regenerative medicine. The marker system of this invention has been used to screen feeder cells, media additives, and culture conditions that promote proliferation of stem cells without differentiation. A culture system optimized by following these markers is suitable for rapid expansion of undifferentiated cells from existing lines, or the derivation of new lines that are equally apposite for clinical use.

Marker system for preparing and characterizing high-quality human embryonic stem cells

This invention provides a system for producing differentiated cells from a stem cell population for use wherever a relatively homogenous cell population is desirable. The cells contain an effector gene under control of a transcriptional control element (such as the TERT promoter) that causes the gene to be expressed in relatively undifferentiated cells in the population. Expression of the effector gene results in expression of a cell-surface antigen that can be used to deplete the undifferentiated cells. Model effector sequences encode glycosyl transferases that synthesize carbohydrate xenoantigen or alloantigen, which can be used for immunoseparation or as a target for complement-mediated lysis. The differentiated cell populations produced are suitable for use in tissue regeneration and non-therapeutic applications such as drug screening.

Growing community of inventors

San Francisco, CA, United States of America

Joseph D Gold