TBCE and dry eye syndrome: Although the Exo-srIκB-laden KCs could not be detected after 1 h (Figure S1a), Exo-srIκB was delivered to about 8% of KCs at low dose (KC:Exo-srIκB = 1:1000) and 70% at high dose (KC:Exo-srIκB = 1:10,000) after 3 h of treatment (Figure 3a-c).