{'fraction_non_alphanumeric': 0.032843560933448576, 'fraction_numerical': 0.027657735522904063, 'mean_word_length': 5.85207100591716, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Cultivation of attenuated hepatitis A virus antigen in a titanium static mixer reactor

The titanium static mixer reactor, demonstrated for a variety of vaccine processes during the late 197s, was investigated for the production of attenuated hepatitis A virus antigen from anchorage‐dependent MRC‐5 cells. This reactor system used Charles River Biotechnological Services cabinets for monitoring and process control. Cell inoculation protocols, using 6000−10,000 cells/cm2, resulted on over 95% attachment at both the laboratory and pilot scales. Indirect monitoring techniques using oxygen, glucose, L‐serine, and L‐glutamine uptake rates were indicative of cell growth prior to virus inoculation as well as environmental and/or nutrient limitations. Seven laboratory‐scale (3900 cm2) runs and one pilotscale (265,000 cm2) run were conducted to investigate refeeding regiments, parallel versus perpendicular element orientation, increased element surface area per unit volume, and scale‐up performance. In general, lysate antigen yields achieved were similar to those of parallel T‐flasks cultivated under similar conditions. © 1994 John Wiley & Sons, Inc.