Virus-specific activity of CTL as determined by IFN-γ ELIspot assay. T-cell specificity and cytokine production were assessed using the IFN-γ ELIspot assay by direct stimulation with hexon pepmix (adenovirus), penton pepmix (adenovirus), irradiated EBV-LCL at an E/T ratio of 1:1 (EBV), and an irrelevant pepmix (control). Results are presented as SFCs/10⁵ CTLs. Lines made from haploidentical donors are represented by circles (n = 8), and those made from matched unrelated donors are represented by triangles (n = 12).