CXCR3 and temporal arteritis: Since GCA patients had higher frequencies of CXCR3+ CD8+ T cells and higher systemic levels of the ligands CXCL9, -10 and -11, Samson et al. hypothesized that CXCR3-expressing CD8+ T cells migrate to the tissue in response to those chemokines, and subsequently become activated by an unknown trigger.