Optical Spectroscopy for the Quality Control of ATMP Fabrication: A New Method to Monitor Cell Expansion and to Detect Contaminations

Abstract

Fabrication of Advanced Therapy Medicinal Products takes currently place in clean and sterile environment and is highly sensitive to any contamination sources. It lasts for several days and is extremely expensive. Quality controls must be performed throughout the process, especially to monitor cell growth during the expansion phase and to detect any contaminations. Regular sampling of the bioreactor's content is required and subsequent biological investigation are conducted. Major drawbacks are first, a delayed result of the quality control and second, an added risk to induce new contaminations when sampling the content of the bioreactor. Here, we present a real time optical spectroscopy method which can be used in a closed system manner, hence reducing the risk of sampling-related contamination. Analysing the shape of the absorption spectrum of the bioreactor content allows monitoring the cell growth and alerting users in case of contamination. Cell concentrations are measured with an accuracy of ± 5% and contamination can be detected about 3 hours after it occurred. This allows stopping the fabrication as soon as a problem arises leading to several tens of thousand dollars savings. Consequently, the price of these products should be greatly reduced and they may be proposed to more patients.

White light spectroscopy for T-cell culture growth monitoring: towards a real-time and sampling free device for ATMPs production

“…Depending on the optical detection scheme employed together with the flow cytometer, counting cells and assessing some of their biological properties for quality control could be performed simultaneously. Adaptation in a close-loop system is straightforward if a derivation is added to the bioreactor as proposed in [2,3]. Indeed, cell counting methods described above all imply considering cells one by one in order to assess culture concentrations and most require sampling of small volumes poorly representative of what really occurs in the bioreactor.…”

“…Using such methods means considering the global "light-culture" interaction rather than estimating concentration counting individual particles. In [2,3], we proposed proofs of concept using white light spectroscopy to measure B-cell concentration and possibly detect contaminations in real-time (the latter was not yet experimentally demonstrated). Detecting contamination is part of quality controls regularly performed during ATMP production.…”

“…Optical methods allow contactless measurements on large volumes. The condition is to use either absorption probes or solution derivation [2,3]. The latter should be preferred as it is contactless, improves solution homogeneity, hence the OCM accuracy, and decreases the dividing times.…”

“…This project encourages research and development of new analysis technologies allowing a real time monitoring of all production stages of biopharmaceutical drugs. Concerning ATMPs, the whole production process is quite complex [1] and the above-mentioned quality controls are frequently performed, especially during the expansion phase [2,3]. Multiplying these controls, and therefore samplings, also increases the risk of introducing new contaminations.…”

Absorption Spectra Description for T-Cell Concentrations Determination and Simultaneous Measurements of Species during Co-Cultures

“…This project encourages research and development of new analysis technologies allowing real-time monitoring of all production stages of biopharmaceutical drugs. Concerning ATMPs, the whole production process is quite complex [ 2 ], and the above-mentioned quality controls are frequently performed, especially during the expansion phase [ 3 , 4 ]. Multiplying these controls, and therefore samplings, increases the risk of new contaminations.…”