Rescue of ADA-inhibited FTOCs with an adenosine kinase inhibitor does not prevent inhibition of SAH hydrolase. FTOCs were performed with C57BL/6 thymuses at day 15 of gestation with media, 5 μM dCF, 1 μM 5′A5′dAdo, or 5 μM dCF plus 1 μM 5′A5′dAdo. After 3 days, SAH hydrolase enzyme activity was assessed in extracts of 25–30 fetal thymic lobes. The data are represented as the means (+ SD) of two independent experiments, each assayed in duplicate.