Predictive Value of Trypan Blue Exclusion Viability Measurements for Colony Formation in a Human Tumor Cloning Assay

Specimens (173) were evaluated to assess the predictive value of cell viability as measured by Trypan Blue exclusion on colony formation in a human tumor cloning system. Overall, there was no significant correlation between Trypan Blue exclusion-determined viability and colony formation in soft agar for these specimens (p = 0.43). This lack of significant correlation was maintained for primary, metastatic, solid, and fluid tumor specimens. These data suggest that, in this soft agar system, specimens containing cells with low Trypan Blue exclusion viability should not be excluded from testing, and that it may not be advantageous to plate on the basis of "viable cells" as measured by Trypan Blue exclusion.