Over the last five years, we have tested over 50 primary human hepatocyte lots, from various cell suppliers, and >60% of them failed to meet our acceptable performance criteria, the majority failed to even form 3D liver microtissues. We calculate that identifying two donors that pass our validation procedures costs around $10-15K and a 100+ hours of a scientist’s time – but this is time well spent. By using pre-validated cells, you will benefit from cross experiment consistency, and improved data robustness.