To detect cell cross-contamination and verify the origin of the cells of an
artificial organ, the sensitive isoenzyme assay was chosen to monitor the
quality test of cell-based devices. Authoritative cell evaluation of artifi
cial skin products has been established in this study. Human and porcine ce
ll suspensions with total cell counts of between 1 x 10(5) and 4 x 10(6) we
re individually tested to determine the activity of isoenzymes. Human fibro
blast, mixed with 1% to 100% of porcine fibroblast, could be significantly
distinguished in the isoenzyme assay. Based on the glucose-6-phosphophate-d
ehydrogenase analysis, the human fibroblast tested in this study belonged t
o the B type human cells. Lactate dehydrogenase (LD), malate dehydrogenase
(MD) and mannose phosphate isomerase isoenzyme (MPI) activities obviously r
evealed that a different pattern corresponds to the percentage of human and
porcine cell mixtures. The discriminatory limit of MPI, LD and MD activity
can reach up to 1% of sensitivity of the isoenzyme analysis. This sensitiv
e isoenzyme analysis method allows us to routinely test cellular biomateria
ls whether interspecies cell line cross-contamination has occurred in the d
evelopment of artificial organs.