Forced degradation of cell-based medicinal products guided by flow imaging microscopy: Explorative studies with Jurkat cells

A.D Grabarek,W Jiskoot,A Hawe,K Pike-Overzet,T Menzen

doi:10.1016/j.ejpb.2021.07.004

Abstract

Cell-based medicinal products (CBMPs) offer ground-breaking opportunities to treat diseases with limited or no therapeutic options. However, the intrinsic complexity of CBMPs results in great challenges with respect to analytical characterization and stability assessment. In our study, we submitted Jurkat cell suspensions to forced degradation studies mimicking conditions to which CBMPs might be exposed from procurement of cells to administration of the product. Flow imaging microscopy assisted by machine learning was applied for determination of cell viability and concentration, and quantification of debris particles. Additionally, orthogonal cell characterization techniques were used. Thawing of cells at 5 °C was detrimental to cell viability and resulted in high numbers of debris particles, in contrast to thawing at 37 °C or 20 °C which resulted in better stability. After freezing of cell suspensions at −18 °C in presence of dimethyl sulfoxide (DMSO), a DMSO concentration of 2.5% (v/v) showed low stabilizing properties, whereas 5% or 10% was protective. Horizontal shaking of cell suspensions did not affect cell viability, but led to a reduction in cell concentration. Fetal bovine serum (10% [v/v]) protected the cells during shaking. In conclusion, forced degradation studies with application of orthogonal analytical characterization methods allow for CBMP stability assessment and formulation screening.

Highlights

The number of cell-based medicinal products (CBMPs) entering clinical trials and being approved by major regulatory bodies for com mercial use is consistently increasing each year [1]
Despite the prom ising clinical data emerging from the use of these innovative therapeutic products, many challenges remain in the areas of manufacturing, formulation development and analytical characterization [2,3]
Jurkat cell suspensions were submitted to thawing at three defined temperatures, freeze-thawing in the presence of different dimethyl sulfoxide (DMSO) con centrations and shaking in absence and presence of FBS

Summary

Introduction

The number of cell-based medicinal products (CBMPs) entering clinical trials and being approved by major regulatory bodies for com mercial use is consistently increasing each year [1]. With clinical site-specific handling procedures, differences in processing and administration of the product will occur [5] Such diverse and multistep production and handling processes expose cells to a range of intended and/or accidental environmental stress factors, such as freezethawing, surface related stress (i.e., mechanical stress), thermal and oxidative stress. Examination of the impact of formulation parameters on cell stability under these stress conditions should be considered to better understand the sensitivity of the product to the stress factors involved This will likely contribute to new insights that can be employed to mitigate the potential risk of therapeutic failure and the occurrence of serious adverse effects due to poor product quality [6,7]

Methods

Results

Discussion

Conclusion