A, mCLCA1 gene-specific primers. Lane 1, PCR control (water alone); lanes 2 and 3, controls omitting reverse transcriptase for mIMCD-K2 and mouse kidney mRNA samples; M, molecular size ladder; lane 4, mIMCD-K2 cell line; lane 5, positive control mouse kidney. B, CFTR gene-specific primers. Lane 1, PCR control; lanes 2 and 3, minus reverse transcriptase controls for mIMCD-K2 and T84; M, molecular size ladder; lane 4, mIMCD-K2 cell line; lane 5, positive control, T84 cell line.