Chinese hamster ovary (CHO) cells, producing human recombinant tissue plasminogen activator (tPA), were grown with mannose (5, 20 and 40 mM) instead of glucose at 31, 33 and 37A degrees C. The highest tPA concentration (1.5 mg l(-1) at 144 h of cultivation) and tPA specific production rate (47 ng 10(-6) cell h(-1)) were obtained at 31A degrees C and 40 mM mannose. Regardless of the temperature or mannose concentration used, an inverse relationship between the specific growth rate and tPA specific production rate was observed, suggesting that tPA production rate would be directly controlled by the growth rate.