To examine the role of Sts-1 and Sts-2 in reactivation from latency at 16 dpi, we performed a limiting dilution plating assay wherein serial dilutions of intact splenocytes are co-cultured with a monolayer of mouse embryonic fibroblasts that are monitored for cytopathic effect at two and three weeks post infection. This evidence concerns the gene UBASH3A and infection.