CD4 and triple-A syndrome: Yin et al. (2010) reported a considerably lower level of FOXP3 expression in peripheral CD4+CD25+ T cells and a lower frequency of CD4+CD25+FOXP3+ T cells in patients with AAA. Similarly, we found that the fraction of CD4+IL-10+ T cells was much lower in AAA lesion model animals. Interestingly, miR-9-5p therapy increased the fraction of CD4+IL-10+ T cells in AAA lesion model animals, indicating a substantial positive connection.