Orbitally shaken bioreactors (OSRs) support the efficient cultivation of mammalian cells in suspension at various scales of operation. Here we introduce a disposable culture vessel with a ventilated cap having a nominal volume of 600 mL (TubeSpin (R) bioreactor 600) for medium-scale cell cultivation. It has a conical bottom designed to fit into a standard swinging bucket rotor to facilitate cell/liquid separation by centrifugation. At shaking frequencies suitable for mammalian cell cultivation (140-220 rpm), the volumetric mass transfer coefficient (k(L)a) ranged from 15 to 40 h(-1), the mixing time was less than 20 s, and the specific power consumption ranged from 0.03 to 0.5 kW/m(3). To define the working conditions for the TubeSpin (R) bioreactor 600, we measured cell growth and environmental culture conditions such as pH and dissolved O-2 and CO2 concentrations over a range of shaking frequencies and working volumes using a stable CHO-derived cell line expressing a human IgG antibody. The optimal cultivation conditions were observed at working volumes of 300-500 mL and shaking frequencies of 180-220 rpm. In 300-mL batch cultures of the same cell line in a TubeSpin (R) bioreactor 600, 1-L cylindrical glass bottle, and 1-L Erlenmeyer shake flask, the maximum cell densities and recombinant antibody yields were similar. This study demonstrated the suitability of the TubeSpin bioreactor 600 for cell culture applications with suspension-adapted CHO cells at culture volumes up to 500 mL. (C) 2013 Elsevier B.V. All rights reserved.