ITGB1 and infection: More specifically, CD29, or β1 integrin, which heterodimerizes with α4 to form VLA-4 and has been demonstrated to be critical for translocation of T cells across the blood brain barrier, [21], is increased in expression on Tregs early post infection in the chronic RIX, but not in RIX lines with a traditional disease course (Fig 5B), suggesting that the suppressive capacity of Tregs cells are critical in setting mice up for chronic infection.