Comment on

• Identification of an alternative CTLA-4 ligand costimulatory for T cell activation.

  Hathcock KS, Laszlo G, Dickler HB, Bradshaw J, Linsley P, Hodes RJ. Hathcock KS, et al. Science. 1993 Nov 5;262(5135):905-7. doi: 10.1126/science.7694361. Science. 1993. PMID: 7694361
• Uncovering of functional alternative CTLA-4 counter-receptor in B7-deficient mice.

  Freeman GJ, Borriello F, Hodes RJ, Reiser H, Hathcock KS, Laszlo G, McKnight AJ, Kim J, Du L, Lombard DB, et al. Freeman GJ, et al. Science. 1993 Nov 5;262(5135):907-9. doi: 10.1126/science.7694362. Science. 1993. PMID: 7694362
• Cloning of B7-2: a CTLA-4 counter-receptor that costimulates human T cell proliferation.

  Freeman GJ, Gribben JG, Boussiotis VA, Ng JW, Restivo VA Jr, Lombard LA, Gray GS, Nadler LM. Freeman GJ, et al. Science. 1993 Nov 5;262(5135):909-11. doi: 10.1126/science.7694363. Science. 1993. PMID: 7694363