Cryopreserved leukapheresis material can be transferred from controlled rate freezers to ultracold storage at warmer temperatures without affecting downstream CAR-T cell culture performance and in-vitro functionality

Jiaming Wei; Katherine Chaney; Woo Jin Shim; Heyu Chen; Grace Leonard; Sean O'Brien; Ziyan Liu; Jinlin Jiang; Robert Ulrey

doi:10.1016/j.cryobiol.2024.104889

Cryopreserved leukapheresis material can be transferred from controlled rate freezers to ultracold storage at warmer temperatures without affecting downstream CAR-T cell culture performance and in-vitro functionality

Cryobiology. 2024 Mar 19:115:104889. doi: 10.1016/j.cryobiol.2024.104889. Online ahead of print.

Authors

Jiaming Wei¹, Katherine Chaney¹, Woo Jin Shim¹, Heyu Chen¹, Grace Leonard¹, Sean O'Brien¹, Ziyan Liu¹, Jinlin Jiang¹, Robert Ulrey²

Affiliations

¹ Cell Therapy Technical Operations, R&D Oncology, AstraZeneca, One MedImmune Way, Gaithersburg, MD, USA.
² Cell Therapy Technical Operations, R&D Oncology, AstraZeneca, One MedImmune Way, Gaithersburg, MD, USA. Electronic address: robert.ulrey@astrazeneca.com.

PMID: 38513998
DOI: 10.1016/j.cryobiol.2024.104889

Abstract

Chimeric antigen receptor (CAR) T-cell therapies are increasingly adopted as a commercially available treatment for hematologic and solid tumor cancers. As CAR-T therapies reach more patients globally, the cryopreservation and banking of patients' leukapheresis materials is becoming imperative to accommodate intra/inter-national shipping logistical delays and provide greater manufacturing flexibility. This study aims to determine the optimal temperature range for transferring cryopreserved leukapheresis materials from two distinct types of controlled rate freezing systems, Liquid Nitrogen (LN2)-based and LN2-free Conduction Cooling-based, to the ultracold LN2 storage freezer (≤-135 °C), and its impact on CAR T-cell production and functionality. Presented findings demonstrate that there is no significant influence on CAR T-cell expansion, differentiation, or downstream in-vitro function when employing a transfer temperature range spanning from -30 °C to -80 °C for the LN2-based controlled rate freezers as well as for conduction cooling controlled rate freezers. Notably, CAR T-cells generated from cryopreserved leukapheresis materials using the conduction cooling controlled rate freezer exhibited suboptimal performance in certain donors at transfer temperatures lower than -60 °C, possibly due to the reduced cooling rate of lower than 1 °C/min and extended dwelling time needed to reach the final temperatures within these systems. This cohort of data suggests that there is a low risk to transfer cryopreserved leukapheresis materials at higher temperatures (between -30 °C and -60 °C) with good functional recovery using either controlled cooling system, and the cryopreserved materials are suitable to use as the starting material for autologous CAR T-cell therapies.

Keywords: Cell therapy; Chimeric antigen receptor; Conduction cooling; Controlled rate freezer; Cryopreservation; LN2-Based cooling; Leukapheresis; Nucleation; Process development.