UV-inactivated EBV retains its inhibitory activity.

Purified CD14⁺ monocytes were infected with replication-competent or inactivated virus. B95.8 supernatants were inactivated by exposure to a 254-nm UV light source for 5 minutes from a distance of 10 cm. The dose corresponded to double the amount required to abolish the transformation of freshly isolated B lymphocytes and the induction of EBNA expression in the EBV-negative B-lymphoma line Bjab. The efficiency of inactivation was confirmed by the failure to detect EBV-specific mRNAs by RT-PCR at different times after infection (not shown). Results from 1 of 5 representative experiments are shown. Mean ± SD of triplicates.