REG-4 is a calcium-independent lectin with mannose-binding specificity that retains carbohydrate recognition activity even in acidic environments. Its ability to act independently of calcium indicates its potent and versatile lectin activity. REG-4 Protein, Human (HEK293, His) is the recombinant human-derived REG-4 protein, expressed by HEK293 , with C-6*His labeled tag.