This assay not only enables an
evaluation of all BoNT intoxication steps but also totally
replaces animal-based potency tests (Alder et al., 2010).
However, developing a cell-based assay as a routine batchrelease
test is difficult because reliable sensitivity is not
guaranteed unless a suitable and stable cell source is
assured. A number of reports have described the origin and
species of cells useful for this assay but it is still controversial
(Alder et al., 2010).