CD44 and type 1 diabetes mellitus: Coronin 1A has an established role in supporting T-cell trafficking and survival (Föger et al., 2006; Mueller et al., 2008; Shiow et al., 2008), and flow cytometric studies confirmed marked deficiency of circulating T cells (expressing high CD44 levels) in Coro1aH130R/H130R mice (Fig. S2) in accordance with the observed suppression of T1D.