In the in vivo CEC mice dry eye experiment, mice treated with the fraction of < 10 kD and < 3 kD had higher tear secretion level (Fig. 3B), stronger expression of ZO-1 and MUC4 (Fig. 4), higher goblet cell density (Fig. 5), and better-preserved microvilli (Fig. 6). Here, MUC4 is linked to Keratoconjunctivitis sicca.