Intriguingly, ERp57 has been detected in the extracellular space of different cell types, for example, to suppress complement activation or as an early sign of renal fibrosis onset (Dihazi et al., 2013; Eriksson et al., 2019), suggesting that ERp57 might have different, currently unknown, extracellular functions. The gene discussed is PDIA3; the disease is renal fibrosis.