CCNA2 and cytomegalovirus infection: When using samples under the identical HCMV infection conditions in HFFs (four days post-infections), one of the strongest levels of pUL97 interaction was found for cyclin H (Table 3; relative WSC of 13) compared to other types of human cyclins, namely cyclins A, B1, E or T1 (WSC 5, b.c., 3 or 3, respectively), while cyclins B2 and D1 were negative.