NK Cell CDM FAQ



Q. What cell sources were used to expand NK cells with PRIME-XV NK Cell CDM?

A. We have used commercially-available frozen Peripheral Blood Mononuclear Cells (PBMCs) and the immortalized cell line NK92.


Q. In the case of PBMCs, as a starting material, were NK cells isolated prior to expansion?

A. No, the entire PBMC population was expanded, under conditions that favor expansion of NK cells. No negative or positive selection method was applied.


Q. Is adaptation required when transitioning from a serum-containing media to PRIME-XV NK Cell CDM?

A. In the case of PBMC-derived NK cell expansion, cells were thawed and directly expanded into PRIME XV NK Cell CDM. No adaptation to serum-free conditions was necessary.

NK92 used had been expanded in media containing 10% FBS prior to experiments with PRIME XV NK Cell CDM. No sequential adaptation into lower FBS percentage was required.

However, if you experience an increase in doubling time ,or any impact in cell culture parameters in your setup, please consider a sequential adaptation into lower serum-containing conditions before fully transitioning into PRIME XV NK Cell CDM. This is particularly relevant if cells have been grown in serum-containing conditions for multiple passages prior to use of chemically-defined media.


Q. What maximum cell density can the media support?

A. We have tested up to 5 million cells/mL successfully. However, the maximum cell density has not been determined.


Q. What types of feeder cells were used? Where they genetically modified?

A. No, we have used non-genetically modified K562 in the feeder cell experiments. Use of cell lines, such as K562-mb15-41BBL, have a different activation ability and may require optimization of protocol and feeding scheme.


Q. What cytokines were used in-house to expand NK cells?

A. IL-2 has been used with both PBMC and NK92 cells.


Q. Does the media contain any cytokine or growth factor?

A. No, PRIME-XV NK Cell CDM is a complete basal media and does not contain cytokines or growth factors. Appropriate supplementation of cytokines is up to the end user and the particular application.


Q. Does the media contain glutamine?

A. Yes, our media contains glutamine.


Q. Does the media contain antibiotics?

A. No, there is no antibiotic present in the media. However, if there is a need to incorporate it, custom media can be provided. Please contact us for more information.


Q. Does the media contain a pH indicator, such as phenol-red?

A. No, the media does not contain phenol red. However, if it is needed, it can be added. For more information please contact us.


Q. Is PRIME-XV NK Cell CDM a chemically-defined and animal component-free medium?

A. Yes, please see definition of chemically define and animal component-free below.


Q. What is Irvine Scientific’s definition of chemically-defined media (CDM)?

A. Irvine Scientific chemically-defined media or CDM products do not contain any undefined animal-derived raw materials and are free of any animal-derived components, including human plasma or human blood-derived components.

All raw materials are defined and their exact concentrations are known, which can include recombinant proteins.


Q. What is Irvine Scientific’s definition of animal component-free (ACF)?

A. Irvine Scientific ACF products are manufactured with raw materials that do not contain any animal or human-derived products to the tertiary level. They are manufactured using equipment that does not come in contact with any animal or human products. The raw material handling, storage, and final product manufacture and packaging are done in a dedicated human and animal component-free facility and equipment.