On the Cover

The cover shows end-on representation of the extended helical epitope of native 2-8 polysialic acid (left) and its biochemically engineered analog (right). Expression of the latter on tumor cells introduces on their surface a distinguishing and highly cytotoxic tumor marker (Courtesy of Dr. Jean-Robert Brisson and Tom Devecseri). Details can be seen in the paper by Liu et al., pages 32832-32836.32832