Cytotoxic T lymphocyte antigen-4 (CTLA-4) regulates primary and secondary peptide-specific CD4(+) T cell responses.

Chambers CA, Kuhns MS, Allison JP. "Cytotoxic T lymphocyte antigen-4 (CTLA-4) regulates primary and secondary peptide-specific CD4(+) T cell responses." Proc. Natl. Acad. Sci. U.S.A.. 1999;96(15):8603-8.