Patent 11952586 was granted and assigned to Hoffmann-La Roche Limited on April, 2024 by the United States Patent and Trademark Office.
Herein is reported a method for the co-cultivation of single deposited B-cells, which can be of any source, with EL-4 B5 feeder cells in a suitable co-cultivation medium. In the herein reported methods the EL-4 B5 cells have been irradiated with a dose of less than 40 Gy, preferably 9.5 Gy or less. Thereby the EL-4 B5 cells have a higher viability and maintain the ability to divide in cultivation at doses less than 6 Gy.