IgG S1 concentration over time for each patient. Thin lines depict previously uninfected patients (red) and previously infected patients (orange); thick lines indicate the median IgG S1 concentrations. Dotted lines specify seroconversion (S1 IgG > 10 BAUs/mL) and sufficient S1 IgG concentration (≥300 BAUs/mL). *P < .05. BEAM, carmustine, etoposide, cytarabine, melphalan.