LC-MS/MS in cultured IPE cells and comparisons with in vivo samples. (A) Overview of procedure for using LC-MS/MS in cultured iris cells. (B) Dorsal and ventral group selection for comparison with Fisher’s exact test. (C) qPCR validation of in vitro proteomics data and comparisons. Student’s t-test for independent samples was used for statistical significance. Equal variances were assumed when Levene’s test p value was greater than 0.05. Asterisk (*) indicates statistical significance (Student t-test; p < 0.05). Each bar represents the average of triplicate values. Error bars represent standard deviation. (D) Pearson correlation between expression of dorsal in vivo proteins at indicated days and expression of dorsal in vitro cultured cell proteins. (E) Pearson correlation between expression of proteins in vivo in the ventral iris at indicated days and expression of proteins in cultured ventral IPE cells.