Cell therapy bioprocessing is a discipline that bridges the fields of cell therapy and bioprocessing (i.e., biopharmaceutical manufacturing), and is a sub-field of bioprocess engineering. The goals of cell therapy bioprocessing are to establish reproducible and robust manufacturing processes for the production of therapeutic cells.23 Commercially relevant bioprocesses will:
Therapeutic cell manufacturing processes can be separated into upstream processes and downstream processes. The upstream process is defined as the entire process from early cell isolation and cultivation, to cell banking and culture expansion of the cells until final harvest (termination of the culture and collection of the live cell batch).
Aside from technology challenges, concerning the scalability of culture apparatus, a number of raw material supply risks have emerged in recent years[when?], including the availability of GMP grade fetal bovine serum.
The upstream part of a bioprocess refers to the first step in which microbes/cells are grown, e.g. bacterial or mammalian cell lines (see cell culture), in bioreactors. Upstream processing involves all the steps related to inoculum development, media development, improvement of inoculum by genetic engineering process, optimization of growth kinetics so that product development can improve tremendously. Fermentation has two parts: upstream and downstream. After product development, the next step is the purification of product for desired quality. When they reach the desired density (for batch and fed-batch cultures) they are harvested and moved to the downstream section of the bioprocess.
The downstream part of a bioprocess refers to the part where the cell mass from the upstream are processed to meet purity and quality requirements. Downstream processing is usually divided into three main sections: cell disruption, a purification section and a polishing section. The volatile products can be separated by distillation of the harvested culture without pre-treatment. Distillation is done at reduced pressure at continuous stills. At reduced pressure, distillation of product directly from fermentor may be possible. The steps of downstream processing are:
Pogaku Ravindra (13 Aug 2015). Advances in Bioprocess Technology. Springer. p. 424. ISBN 9783319179155. 9783319179155 ↩
Kirouac, D. & Zandstra, P. (2008). "The systematic production of cells for cell therapies". Cell Stem Cell. 3 (4): 369–381. doi:10.1016/j.stem.2008.09.001. PMID 18940729. https://doi.org/10.1016%2Fj.stem.2008.09.001 ↩
Rowley, J.A. Developing Cell Therapy Biomanufacturing Processes, Chem Eng Progress, SBE Stem Cell Engineering Nov Supplement, 50-55, 2010. ↩
Draft Guidance : Instructions and Template for CMC Reviewers of Human Somatic Cell Therapy IND Applications ↩
"Amgen Bioprocessing Center (ABC)". www.kgi.edu. Archived from the original on 2014-07-04. Retrieved 2014-06-28. https://web.archive.org/web/20140704035758/http://www.kgi.edu/faculty-and-research/kgi-centers/amgen-bioprocessing-center.html ↩
"Bioprocessing". www.kgi.edu. Archived from the original on 2015-03-23. Retrieved 2017-11-17. https://web.archive.org/web/20150323045145/http://www.kgi.edu/academic-programs/master-of-bioscience-(mbs)/career-majors/bioprocessing.html ↩