MEJORA DE LA CALIDAD DEL PRODUCTO EN PROCEDIMIENTOS DE CULTIVO DE CELULAS DE MAMIFERO PARA LA PRODUCCION DE PROTEINAS

Un procedimiento de cultivo celular para la producción de una molécula de CTLA4 soluble, que comprende: a) cultivar células CHO que producen una molécula de CTLA4 soluble en cultivo celular en condiciones que permiten la producción de CTLA4; y b) alimentar las células con D-galactosa. The present invention describes methods and processes for the production of proteins, particularly glycoproteins, by animal cell or mammalian cell culture, illustratively, but not limited to, fed-batch cell cultures. The methods comprise feeding the cells with D-galactose, preferably with feed medium containing D-galactose, preferably daily, to sustain a sialylation effective level of D-galactose in the culture for its duration, thus increasing sialylation of the produced proteins. The methods can also comprise at least two temperature shifts performed during the culturing period, in which the temperature is lower at the end of the culturing period than at the time of initial cell culture. The cell culture processes of the invention involving two or more temperature shifts sustain a high cell viability, and can allow for an extended protein production phase. The methods can also comprise the delayed addition of polyanionic compound at a time after inoculation. Supplementation of the cultures with D-galactose, preferably in a feed medium, to sustain galactose at sialylation effective levels in the cultures until the end of a culture run reverses a decline in sialylation that accompanies culture scale up, and is advantageous for large scale culturing processes.