ABSTRACT
Acknowledgments ............................................................................................ 562
Appendix .......................................................................................................... 563
References ........................................................................................................ 564
In this chapter we summarize the data available about the toxicity of cell-penetrating
peptides (CPPs). The major part of the data available concerns the in vitro
toxicity of CPPs, that is their effects on the viability of cultured cells. In general, the
classical definitions of cell viability include the exclusion of Trypan Blue as an
indicator of membrane integrity and colony formation to determine whether cells
can continue to proliferate.1 Nowadays, the choice of viability/toxicity assays is not
restricted to those two classical assays; instead, a whole spectrum of assays and their
variants is commercially available. In this chapter we discuss the methods that have
been used to determine the toxic effects of CPPs and point out some nuances which
should be taken into consideration when working with these peptides. We also
briefly summarize the data available about the hemolytical activity of CPPs and
about their toxicity in vivo.
