Table 3.

Comparison of commonly used allogeneic NK cell sources

NK source	Advantages	Limitations
PB-NK cells	Relatively easy to collect Good in vivo expansion Good clinical track record	Heterogeneous cell population Challenging to genetically modify Can only give one dose
UB-NK cells	NK Progenitors and CD34 + present Higher percentage of NK cells The ability to cryopreserve UCB	Heterogeneous cell population
NK92 cells	Defined, homogeneous cell population Easy to expand Easy to genetically modify Can give multiple doses	Tumor cells Irradiated Lack certain receptors, e.g., CD16 limited in vivo expansion
iPSC-NK cells	Defined, homogeneous cell population Circumvent issues with donor sourced cells (donor selection, contaminating T, B) Potential for in depth preclinical testing Defined genetic makeup Easy to genetically modify at iPSC stage Can give multiple doses Can engineer multiple enhancements Don’t need to irradiate- good in vivo survival Suitable for “off-the-shelf” multicancer NK cell therapy	More complicated to produce