IMMUNOLOGY. For the article “Activation of antitumor cytotoxic T lymphocytes by fusions of human dendritic cells and breast carcinoma cells” by Jianlin Gong, David Avigan, Dongshu Chen, Zekui Wu, Shigeo Koido, Masahiro Kashiwaba, and Donald Kufe, which appeared in number 6, March 14, 2000, of Proc. Natl. Acad. Sci. USA (97, 2715–2718), the authors note the following. In the key terms, DF3A should read DF3.