Abstract: Provided are a method for preparing a highly versatile aqueous solution having remarkably improved membrane filterability, which can be stably membrane-filtered in a short time, an aqueous solution prepared by the preparation method, a method for culturing cells using the aqueous solution which is prepared by the preparation method, a method for producing a physiologically active substance using the culturing method, a physiologically active substance produced by the method for producing a physiologically active substance, a method for performing membrane filtration of the aqueous solution which is prepared by the preparation method of the aqueous solution, a method for improving membrane filterability of the aqueous solution, and a method for producing the physiologically active substance by preparing the aqueous solution, performing membrane filtration of the aqueous solution, and then culturing cells using the resulting aqueous solution.

Abstract: The present invention relates to a process for producing a desired polypeptide using rat cells. Specifically, the present invention relates to a process for producing the polypeptide which comprises culturing rat cells such as YB2/3HL.P2.G11.16Ag.20 (hereinafter referred to as YB2/0), preferably rat cells to which a recombinant DNA comprising DNA encoding a desired polypeptide such as an immunologically functional molecule is introduced, in a medium which does not contain serum (hereinafter referred to as a serum-free medium). Among the desired polypeptides obtained by the process of the present invention, an antibody obtained by using a transformant of YB2/0 has a high antibody-dependent cell-mediated cytotoxic activity (hereinafter sometimes referred to as ADCC activity) and is useful as a pharmaceutical agent.

Abstract: Provided are a method for preparing a highly versatile aqueous solution having remarkably improved membrane filterability, which can be stably membrane-filtered in a short time, an aqueous solution prepared by the preparation method, a method for culturing cells using the aqueous solution which is prepared by the preparation method, a method for producing a physiologically active substance using the culturing method, a physiologically active substance produced by the method for producing a physiologically active substance, a method for performing membrane filtration of the aqueous solution which is prepared by the preparation method of the aqueous solution, a method for improving membrane filterability of the aqueous solution, and a method for producing the physiologically active substance by preparing the aqueous solution, performing membrane filtration of the aqueous solution, and then culturing cells using the resulting aqueous solution.

Abstract: The present invention provides a medium suitable for animal cell culture, a culture method using the same, and the like. The present invention relates to a method for culturing animal cells having an ability to produce a substance, which comprises culturing the animal cells in a medium supplemented with an oligopeptide having one or more L-cysteines and excluding glutathione, a method for producing a substance by culturing animal cells having the ability to produce the substance, which comprises culturing the animal cells in a medium supplemented with an oligopeptide having one or more L-cysteines and excluding glutathione to produce and accumulate the substance in the culture, and collecting the substance from the culture, and a culture medium comprising an oligopeptide having one or more L-cysteines and excluding glutathione.

Abstract: The present invention relates to a process for producing a desired polypeptide using rat cells. Specifically, the present invention relates to a process for producing the polypeptide which comprises culturing rat cells such as YB2/3HL.P2.G11.16Ag.20 (hereinafter referred to as YB2/0), preferably rat cells to which a recombinant DNA comprising DNA encoding a desired polypeptide such as an immunologically functional molecule is introduced, in a medium which does not contain serum (hereinafter referred to as a serum-free medium). Among the desired polypeptides obtained by the process of the present invention, an antibody obtained by using a transformant of YB2/0 has a high antibody-dependent cell-mediated cytotoxic activity (hereinafter sometimes referred to as ADCC activity) and is useful as a pharmaceutical agent.

Abstract: The present invention relates to a process for producing a desired polypeptide using rat cells. Specifically, the present invention relates to a process for producing the polypeptide which comprises culturing rat cells such as YB2/3HL.P2.G11.16Ag.20 (hereinafter referred to as YB2/0), preferably rat cells to which a recombinant DNA comprising DNA encoding a desired polypeptide such as an immunologically functional molecule is introduced, in a medium which does not contain serum (hereinafter referred to as a serum-free medium). Among the desired polypeptides obtained by the process of the present invention, an antibody obtained by using a transformant of YB2/0 has a high antibody-dependent cell-mediated cytotoxic activity (hereinafter sometimes referred to as ADCC activity) and is useful as a pharmaceutical agent.

Abstract: The present invention relates to a process for producing a substance, which comprises culturing an animal cell having an ability to produce the substance in a medium containing a ubiquinone such as Q10 until the substance is produced and accumulated in the culture, and recovering the substance therefrom, and a method of improving the productivity of a substance, which comprises culturing an animal cell having an ability to produce the substance in a medium containing a ubiquinone.