<P> Chinese hamster ovary (CHO) cells are an epithelial cell line derived from the ovary of the Chinese hamster, often used in biological and medical research and commercially in the production of therapeutic proteins . They have found wide use in studies of genetics, toxicity screening, nutrition and gene expression, particularly to express recombinant proteins . CHO cells are the most commonly used mammalian hosts for industrial production of recombinant protein therapeutics . </P> <P> The Chinese hamster had been used in research since 1919 where they were used in place of mice for typing pneumococci . They were subsequently found to be excellent vectors for transmission of kala - azar (a.k.a. visceral leishmaniasis), facilitating leishmania research . </P> <P> In 1948, the Chinese hamster was first used in the United States for breeding in research laboratories . In 1957, Theodore T. Puck obtained a female Chinese hamster from Dr. George Yerganian's laboratory at the Boston Cancer Research Foundation and used it to derive the original Chinese hamster ovary (CHO) cell line . Since then, CHO cells have been a cell line of choice because of their rapid growth in suspension culture and high protein production . </P> <P> Having a very low chromosome number (2n = 22) for a mammal, the Chinese hamster is also a good model for radiation cytogenetics and tissue culture . </P>

Chinese hamster ovary cho mammalian cell expression system