Time course of naive CD4 and CD8 T-cell counts after treatment for HD. The naive CD4 and CD8 T-cell counts are plotted versus years after completion of treatment for all subjects in this study who had been treated for HD (n = 56). Counts for 34 healthy individuals are shown on the right for comparison (gray lines indicate the medians for the control group). The inset for each graph shows a magnification of the acute recovery phase, lasting about 1.5 years.