CD4 and systemic lupus erythematosus: In the analysis of the haplotypes, we found that the T + A haplotype was a protective factor for developing AS; however, Löfgren et al. analyzed three SNPs of DNAM-1 (rs763361, rs34794968, and rs727088) and reported that the ATC haplotype was a risk factor for developing SLE, and that this was related to a decrease in the expression of DNAM-1 in CD4, CD8+, and NK T lymphocytes, but not in NK cells [17].