CTLA4又稱CTLA-4(細胞毒性T淋巴細胞相關抗原4,cytotoxic T-lymphocyte-associated protein 4)或CD152(分化群152),是一种蛋白质受体[7]。CTLA-4蛋白由小鼠的Ctla4[8]和人类的CTLA4基因编码[9]。CTLA-4于1991年首次被發現[10]。
^Human Ig superfamily CTLA-4 gene: chromosomal localization and identity of protein sequence between murine and human CTLA-4 cytoplasmic domains. European Journal of Immunology. December 1988, 18 (12): 1901–5. PMID 3220103. doi:10.1002/eji.1830181206.