CHO-K1 is a cell line derived from the ovary of the Chinese hamster, specifically used in biological and medical research. It is a type of Chinese hamster ovary (CHO) cell, which is widely utilized for producing recombinant proteins and studying cellular processes. These cells are favored in biotechnology due to their ability to grow quickly and their capacity for post-translational modifications, which are essential for the proper functioning of many proteins. CHO-K1 cells are often used in the production of therapeutic proteins, including monoclonal antibodies, making them crucial in the development of modern medicines.