TREM2 and arthritic joint disease: Next, we report that 34% of these CXCL13 regions in seropositive tissue volumes co-localized with RASGRP2 overexpression while 47% of regions exhibiting CXCL13 downregulation were enriched for TYROBP. RASGRP2 had previously been implicated in arthritis development in murine models28 and TYROBP, also known as DAP12, when in presence of TREM2 signaling, further antagonizes cytokine production29.