1211 results about "Suspension culture" patented technology

The present invention relates to methods for production of undifferentiated or differentiated embryonic stem cell aggregate suspension cultures from undifferentiated or differentiated embryonic stem cell single cell suspensions and methods of differentiation thereof.

The present invention provides a cell culture medium formulation that supports the in vitro cultivation, particularly in suspension, of mammalian cells, particularly epithelial cells and fibroblast cells, and methods for cultivating mammalian cells in suspension in vitro using these media. The media comprise a basal medium and a polyanionic or polyanionic compound, preferably a polysulfonated or polysulfated compound, and more preferably dextran sulfate. The present invention also provides chemically defined, protein-free eukaryotic cell culture media comprising an iron chelate and zinc, which is capable of supporting the growth (and particularly the high-density growth of mammalian cells) in suspension culture, increasing the level of expression of recombinant protein in cultured cells, and/or increasing virus production in cultured cells.

Human/human hybrid cells were made via fusion of human embryonic kidney cells (293S) and modified Burkitt's lymphoma cells (2B8). The fusion cells are useful as host cells for the recombinant expression of mammalian genes. The advantages of using these hybrid clones of human kidney- and B-cells, called HKBs, for mammalian gene expression, include (i) the cells are negative for immunoglobulin expression, (ii) the cells grow easily in plasma protein-free medium (with or without the addition of recombinant insulin) as suspension cultures in a shake flask or in a fermenter (iii) the cells are very susceptible for transfection of DNA, and (iv) the cells secrete high levels of heterologous recombinant proteins, such as recombinant monoclonal antibodies, soluble ICAM-1, rIL-4, and rFVIII.

The present invention addresses the need to improve the yields of viral vectors when grown in cell culture systems. In particular, it has been demonstrated that for adenovirus, the use of low-medium perfusion rates in an attached cell culture system provides for improved yields. In other embodiments, the inventors have shown that there is improved Ad-p53 production cells grown in serum-free conditions, and in particular in serum-free suspension culture. Also important to the increase of yields is the use of detergent lysis. Combination of these aspects of the invention permits purification of virus by a single chromatography step that results in purified virus of the same quality as preparations from double CsCl banding using an ultracentrifuge.

The present disclosure describes mammalian pluripotent embryonic-like stem cells (ELSCs) isolated from corneal limbal tissue, a non-embryonic tissue. The ELSCs of the present disclosure are capable of proliferating in an in vitro culture, maintain the potential to differentiate into cells of endoderm, mesoderm, and ectoderm lineage in culture, and are capable of forming embryoid-like bodies when placed in suspension culture. Thus, these cells possess multi-lineage differentiation potential and self-renewing capability. ELSCs may be a promising therapeutic tool, and may provide new therapeutic alternatives for various diseases, conditions, and injuries.

The present invention relates to a method of isolating and culturing mesenchymal stem cells using umbilical cord blood that is most ideal for cell therapy. The method comprises adding an anti-coagulant to umbilical cord blood having a volume of more than 45 ml per unit, which is obtained within 24 hours after parturition; diluting the resulting mixture of the anti-coagulant and umbilical cord blood with an αMEM (alpha-minimum essential medium), followed by centrifugation to harvest monocytes; and subjecting the obtained monocytes into suspension culture in the αMEM containing Stem Cell Factor, GM-CSF (granulocyte-macrophage colony-stimulating factor), G-CSF (granulocyte colony-stimulating factor), IL-3 (interleukin-3) and IL-6 (interleukin-6).

This disclosure provides an improved system for culturing human embryonic stem cells. The cells are cultured in suspension so as to maximize the production capacity of the culture environment. The new culture system of this invention allows for bulk proliferation of hES cells in a more cost-effective manner, which facilitates commercial production of important products for use in human therapy.

The present invention relates to methods for production of undifferentiated or differentiated embryonic stem cell aggregate suspension cultures from undifferentiated or differentiated embryonic stem cell single cell suspensions and methods of differentiation thereof.

The invention discloses a serum-free medium for Madin-Darby canine kidney (MDCK) cell full suspension culture. The serum-free medium for MDCK cell full suspension culture comprises an amino acid part, a vitamin part, an inorganic salt part and other additive parts. The serum-free medium has the beneficial effects that the serum-free medium for MDCK cell full suspension culture, provided by the invention, is high in cell culture density and clear in composition and does not contain animal serum, a downstream product is purified, the product quality is improved, and the serum-free medium is convenient to prepare and use and suitable for large-scale production of influenza vaccines and avian influenza vaccines.

Adipose tissue-derived stromal cells induced to form multicellular aggregates can be formed reliably and consistently, they can be maintained for prolonged periods in adherent or suspension culture, and they are able to survive, grow, and/or differentiate in serum-free media conditions. The present invention provides compositions and methods for the use of such aggregates in tissue repair. This culture platform provides a controlled and defined system in which to study and standardize adult stem cell biology, and begets an instinctive “modular” approach to the predictable replacement and regeneration of adipose tissue.

The invention discloses a large-scale cultivation method and a quality detection method of cordyceps militaris fruit bodies, comprising the steps of: (1) screening spawn; (2) preparing a rice solid culture medium (40-55 parts of rice and 45-60 parts of nutrient solution in every 100 parts by weight) and killing bacteria; (3) preparing liquid spawn: activating the spawn, inoculating the spawn into a liquid culture medium, conducting static culture for 24 hours and performing suspension culture on a shaking table; (4) culturing fruit bodies: inoculating the liquid spawn on the solid culture medium for dark culture for 6 days at the temperature of 20 DEG C until the surface of the medium is covered by mycelium; placing the well grown mycelium under incandescence with light intensity of 100 to 300 lux, wherein during a primordium growth phase, illumination is performed for 20-24 hours per day at the temperature of 20-24 DEG C; and during a fruit bodies growth phase, illumination is performed for 8-12 hours per day at the temperature of 18-20 DEG C and the fruit bodies are harvested 5 to 8 days after mature. The cordyceps militaris fruit bodies cultured by the method have the advantages of high yield and high content of active ingredients. Batches of cordyceps militaris fruit bodies have fingerprints with a similarity value greater than 0.950, indicating stable and controllable quality.

We disclose a particle comprising a matrix coated thereon and having a positive charge, the particle being of a size to allow aggregation of primate or human stem cells attached thereto. The particle may comprise a substantially elongate, cylindrical or rod shaped particle having a longest dimension of between 50 μm and 400 μm, such as about 200 μm. It may have a cross sectional dimension of between 20 μm and 30 μm. The particle may comprise a substantially compact or spherical shaped particle having a size of between about 20 μm and about 120 μm, for example about 65 μm. We also disclose a method of propagating primate or human stem cells, the method comprising: providing first and second primate or human stem cells attached to first and second respective particles, allowing the first primate or human stem cell to contact the second primate or human stem cell to form an aggregate of cells and culturing the aggregate to propagate the primate or human stem cells for at least one passage. A method of propagating human embryonic stem cells (hESCs) in long term suspension culture using microcarriers coated in Matrigel or hyaluronic acid is also disclosed. We also disclose a method for differentiating stem cells.

Disclosed is a Madin-Darby canine kidney (MDCK)-derived cell line. The MDCK-derived cell line is derived from MDCK cells deposited under accession number ATCC CCL-34. The MDCK-derived cell line can be prepared by serum-free culture and suspension culture. Preferably, the MDCK-derived cell line has low or no tumorigenicity. The MDCK-derived cell line is preferably selected from MDCK Sky1023, MDCK Sky10234 and MDCK Sky3851. Further disclosed are a culture method for growing the MDCK-derived cells and a method for producing a vaccine virus using the MDCK-derived cells.

The present invention provides an improved process for the production of recombinant peptides. In particular, the present invention provides an improved process for the production of recombinant peptides in the form of viral capsid fusion proteins which can be assembled in vivo in plant cell suspension cultures. The invention also includes plasmids, sequences, and plant cells which allow for non-infectious viral capsid fusion peptide production.

The invention discloses a serum-free medium for full suspension cultivation of a BHK (Baby Hamster Kidney)-21 cell. The serum-free medium for full suspension cultivation of the BHK-21 cell comprises an amino acid part, a vitamin part, an inorganic salt part and a part of other additives. The medium disclosed by the invention has the beneficial effects that the serum-free medium for full suspension cultivation of the BHK-21 cell is high in culture cell density, clear in component and free from animal serum, facilitates purification of downstream products, and improves the product quality. The medium is convenient to prepare and use, and is applicable to production of biological products on a large scale.

The invention provides BHK-21 cells obtained by high-density suspension culture in a low-serum and serum-free culture medium and a culture method thereof. The culture method comprises the following steps: 1) resuscitating frozen BHK-21 cells and performing adherent culture to obtain adherently cultured BHK-21 cells; 2) subculturing the adherently cultured BHK-21 cells in culture solution to obtain suspension-cultured BHK-21 cells and freezing the BHK-21 cells; 3) performing resuscitation culture of the suspension-cultured BHK-21 cells and performing biological property identification; and 4) performing bioreactor adaptive culture of the suspension-cultured BHK-21 cells identified to be qualified. The invention has the advantages that: a cell domesticating method provided by the invention and the obtained BHK-21 cells which can be cultured in a suspended manner save culture solution and bovine serum, are in accordance of current energy-saving, environment-protection and low-carbon concepts for the application of suspended-cultured cells into actual production saves floor area and labor investment greatly, and create considerable economic benefit and social benefit.

Protoplasts which regenerate reproducibly in a short time to normal, fertile plants can be regenerated from an auxin-autotrophic genotype of Zea mays (L.). Starting from immature embryos on hormone-free media, an auxin-autotrophic, embryogenic callus is formed on the shoot basis of the seedlings, which callus retains its embryogenic potential over a substantial period of time when subcultured on hormone-free medium. In addition to fully-developed embryos, adventitious embryos are also formed under suitable culture conditions (6-9% of sucrose in the medium). When the sucrose content is reduced to 2-3% and 2,4-dichlorophenoxyacetic acid is added, soft, granular calli are formed which consist of embryogenic cell aggregates (type II callus). After subculturing the type II callus in the form of a cell suspension culture, totipotent protoplasts can be isolated. From these protoplasts, the maize plants according to the invention are regenerated.

A cartilage-like biomaterial is bioengineered by using a self-aggregating suspension cell culture with hydrostatic mechanical force without the use of a scaffold or foreign matrix for cell attachment during culture. The cells in suspension culture may be preconditioned prior to application of the hydrostatic mechanical force, such as hydrostatic pressure, for a period of time in the range of about 1 week to about 10 weeks. The cartilage-like biomaterial shares critical structural, phenotype, and functional characteristics with native, intact cartilage tissue.

A microalgae suspension-adhesion mixed culture and separated harvesting method based on a suspended carrier comprises the following steps: on the basis of original microalgae suspension culture, a predetermined amount of solid carrier is added into a culture solution and enabled to suspend in the liquid phase in an aerating or mechanical stirring manner; during cultivation, the microalgae is enabled to attach to a solid carrier to form an algae membrane; the solid carrier is separated to harvest algae cells; the solid carrier from which the algae cells are harvested is recovered for recycling and re-injected into the microalgae culture solution; serving as seeds, the liquid-phase algae cells are re-attached to the solid carrier to grow, so that continuous culture and harvest of the algae cells are realized. Compared with the air floatation, precipitation, centrifugation, filtering and other harvest methods, the microalgae suspension-adhesion mixed culture and separated harvesting method is simple to operate, dispenses with agents, is low in energy consumption, and can realize large-scale and mechanical continuous harvesting, thereby effectively saving the cost in harvesting the algae cells.

The invention discloses a preparation method of an avian influenza virus suitable for growing in a serum-free full-suspended cultured MDCK cell line and the avian influenza virus obtained through the method. The preparation method comprises the following steps of 1 preparation of the MDCK cells to be inoculated; 2 virus seed preparation, wherein a chick embryo source avian influenza virus is prepared; 3 F1 generation virus domestication; 4 F2 generation virus domestication, wherein a supernatant sample retained at the time point when the blood clotting titer of the avian influenza virus obtained in the F1 generation is highest is taken, and the step 3 is repeated; 5 F3 generation virus domestication, wherein the F3 generation virus culturing temperature is 35 DEG C; 6 F4 generation-F10 generation virus domestication, wherein the step 5 is repeated, and the domesticated avian influenza virus is obtained. According to the preparation method, through a domestication method, the avian influenza virus is directly domesticated to completely adapt to be efficiently reproduced on the serum-free full-suspended cultured MDCK cells from the mode of being cultured by a chick embryo, the domestication efficiency is high, the avian influenza virus can be efficiently infected and copied in the MDCK cells, and the virus characteristic is stable.

The invention discloses a serum-free animal origin-free culture medium for suspension culture of BHK-21 cells and a preparation method of the serum-free animal origin-free culture medium. According to the serum-free animal origin-free culture medium for suspension culture of the BHK-21 cells and the preparation method of the serum-free animal origin-free culture medium, through the addition and component optimization of amino acids, inorganic salt, vitamins, lipids, hydrolysates and the rest of additives in the culture medium, the multiplication speed of the BHK-21 cells is remarkably improved, the doubling time is shortened, and the high activity is maintained while the cells reach higher growth density. The culture medium is suitable for high-density suspension culture of the BHK-21 cells, low in cost, free of serum, free of animal origins and low in protein, the biological function of the serum is completely replaced through the addition of the ingredients including the lipids, the vitamins, the microelements, recombinant protein and the hydrolysates,, and some negative effects caused by the serum to later purification and separation of an antigen are avoided. Through optimization on the components of the culture medium, the multiplication speed of the BHK-21 cells in suspension culture is higher, the cell density is higher, the cell activity is higher, and the BHK-21 cells are more suitable for large-scale industrial production.

The invention provides a method for producing rabies viruses by the suspension culture of BHK21 cells, which comprises a step of performing suspension culture of BHK21 cells in bioreactor containing a BHK21 cell culture medium, wherein the conditions for the suspension culture in the step include a temperature of 32 to 36 DEG C, a pH value of 7.0 to 8.0 and a dissolved oxygen concentration of 30 to 50 percent; and the BHK21 cell culture medium comprises the components shown in a table 1. The method overcomes the biases of the prior art and realizes the production of the rabies viruses by the suspension culture of BHK21 cells in the bioreactor. The obtained rabies viruses can be used for producing rabies vaccine. Due to the automatic culture environment parameter control of the bioreactor, the cells grow and the viruses propagate in more favorable environments, the virus titer is improved and the large-scale automatic continuous production can be realized.