Expression of ALAD cDNA in CHO cells.

Transfection of CHO cells with ALAD cDNA, quantitation of human ALAD protein expressed in cells, and assays on ALAD activity were carried out as described previously.8 Specific ALAD activity (A/M ratio) expressed as a percent of the activity expressed by normal ALAD cDNA. Data are the mean of quadruple assays.