CBLN1 and dry eye syndrome: Further, among Cer subclasses, the levels of Cer [NDS], Cer [NP], Cer [ADS], Cer [AH], Cer [AP], Cer [EOS], Cer [EOH] and Cer [EOP], especially Cer [NP] were significantly higher in the SC than in KCs, while Cer [NS] was almost the same level in the SC and in KCs (Fig. 4b).