The formation of varicella-zoster (V-Z) virus-associated antigens was studied in V-Z virus-infected Vero cells by means of indirect immunofluorescence. Early antigen (EA) was first detected inside V-Z virus-infected Vero cells 4 to 6hr after infection, whereas surface membrane antigen (SMA) was expressed on the outer surface of infected cells 2 to 3hr later than EA, and intranuclear late antigen (LA) was detected several hours later than SMA antigen. EA expression was not inhibited by cytosine arabinoside (Ara-C) treatment, whereas LA formation was completely blocked by Ara-C. The presence of two components of SMA early SMA (ESMA) and late SMA (LSMA), was suggested by this difference in susceptibility to Ara-C. The formation of all viral antigens, EA, SMA, and LA, was blocked by inhibitors of RNA and protein synthesis.