Abstract: The new glycoprotein, which possesses an anti-tumor activity, a leukemia cell differentiation inducing activity, a cellular immunology enhancing activity, a vascular endothelial cell growth stimulating activity and a hepatocyte growth stimulating activity, can be obtained.

Abstract: The new glycoprotein, which possesses an anti-tumor activity, a leukemia cell differentiation inducing activity, a cellular immunology enhancing activity, a vascular endothelial cell growth stimulating activity and a hepatocyte growth stimulating activity, can be obtained.

Abstract: A carrier for adhering animal cells during culturing or for immobilization of animal cells is produced by coating a porous substrate with a cell adhesive material in the form of a mixture with chitosan. In a preferred embodiment, the porous substrate is a nonwoven fabric prepared by impregnating a nonwoven fabric web with a binder resin, and the mixture contains silk fibroin, gelatin and chitosan. Coating is carried out by contacting the nonwoven fabric with a solution prepared by adding silk fibroin and gelatin to an acidic aqueous solution of chitosan to coat the nonwoven fabric, drying the coated nonwoven fabric and treating the dried nonwoven fabric with an alkali to render the chitosan insoluble.

Abstract: A process and system for cultivating adhesive cells in a packed bed of solid cell matrix is disclosed. Adhesive cells are adhered to a solid cell matrix, preferably ceramic particles, and packed in a cell culture tank to form the packed bed. The culture medium is circulated through the packed bed in a direction. The circulating of the culture medium is then stopped and the direction of the medium being circulated is reversed. This periodic switching of the direction of the culture medium reduces channelling of the culture medium. The bottom or head of the culture tank can also contain a separator to trap any bubble existing in the culture medium or to trap any quantity of cell matrix possibly running out from the culture tank.

Abstract: Cell cultivation is carried out by proliferating cells in a small preliminary culture tank containing immobilizing carriers, stripping proliferated cells from the carriers, forming a cell suspension of the stripped cells in culture medium in an intermediate reservoir, intermittently transferring the suspension into a main culture tank containing ceramic immobilizing carriers and further culturing the cells. The main culture tank has an inversed funnel-shaped inlet above the carriers with a perforated plate attached to the bottom of the inlet for uniform distribution of cell suspension from above the carriers, and a plate in the form of a net under the carriers on a perforated plate for uniform distribution of cell suspension from beneath the carriers.