- Single-chain Fv-streptavidin substantially improved therapeutic index in multistep targeting directed at disialoganglioside GD2. Cheung, N.K., Modak, S., Lin, Y., Guo, H., Zanzonico, P., Chung, J., Zuo, Y., Sanderson, J., Wilbert, S., Theodore, L.J., Axworthy, D.B., Larson, S.M. J. Nucl. Med. (2004)