CTLA4 and multiple sclerosis: Our earlier study of protein expression showed that the percentage of cells expressing membrane CTLA-4 and cytoplasmic CTLA-4 in multiple sclerosis patients with the relapsing-remitting form of the disease was higher for individuals possessing CT60G>A[A+] alleles than those with the CT60G>A[GG] genotype (Karabon et al. 2009).