Cell culture is fundamental to many research and industrial processes, but traditional transport methods are fraught with challenges. Cryopreservation, the most common technique, requires potentially cytotoxic cryoprotective and can lead to poor cell recovery. Additionally, the logistics of cryopreservation are complex, requiring specialised equipment and careful handling. An ambient temperature transport medium like CellShip could significantly ease these issues.

This study introduces CellShip, a novel transportation medium for mammalian cells. Five commonly used cell lines (HEK293, CHO, HepG2, K562, and Jurkat) were successfully transported and stored at ambient temperature for up to 96 hours, maintaining high cell viability.

Methods of Cell Transportation

Current cell transportation methods largely rely on cryo- preservation, where cells are frozen using cryoprotective agents (CPAs) such as dimethyl sulfoxide (DMSO). This process, though effective, has several drawbacks:

• Logistical Challenges: Requires slow freezing at -1°C per minute to -80°C, storage in liquid nitrogen, and transport on dry ice.
• Cytotoxicity: Prolonged exposure to DMSO can lead to cellular changes and toxicity.
• Recovery Issues: Cells must be thawed quickly to avoid ice crystal formation, followed by careful removal or dilution of DMSO to prevent osmotic shock. Alternatively, cells can be shipped as growing cultures in sealed vessels, which is feasible for short durations but presents risks of contamination and cell detachment, leading to cell death (anoikis).

Development of CellShip

CellShip was developed to address these issues by providing a medium that allows for ambient temperature transport. This eliminates the need for cryopreservatives and reduces the risk of cell damage. The study assessed the viability and cell count of five cell lines (HEK293, CHO, HepG2, K562, and Jurkat) after transport and storage in CellShip for 72 to 96 hours.

Materials and Methods

• Cell Culture Conditions: Cells were cultured at 37°C in a humidified environment with 5% CO2. Specific media formulations were used for different cell lines, all supplemented with 10% foetal bovine serum (FBS).

• Cell Count and Viability: Cell counts, and viability were measured using a CytoSmartTM automated cell counter and Trypan Blue exclusion. Fold changes in cell numbers were calculated before transport, immediately after transport, and following a recovery period.

Morphological Analysis: The morphology of HepG2 cells was examined by phase-contrast microscopy post-recovery.

Transportation Procedure: Cells were transported in 2 mL Nalgene cryovials, placed in polystyrene transport containers, and shipped via commercial courier. Internal package temperature was monitored using a TinyTag data logger.

Cryopreservation Procedure: For comparison, cells were cryopreserved in FBS with 10% DMSO, frozen slowly at -80°C, stored in liquid nitrogen, and transported on dry ice.

Recovery and Sampling: Post-transportation, CellShip suspensions were directly transferred to growth media. Cryopreserved cells were thawed and gradually diluted with pre-warmed media.

Metabolic Activity: Metabolic activity post-transportation was measured using the alamarBlue® reduction assay.