Chronic plerixafor treatment has prolonged effects on blood leukocyte levels in patients with WHIM syndrome. After plerixafor was discontinued and the 6-month trial was completed, the leukocyte subsets indicated to the left of each row were measured in the blood for up to 35 days for the patient indicated at the top of the corresponding column of panels. Horizontal dotted lines indicate the average baseline values before starting treatment. Note that baseline values shown for P3 correspond to P3 (b) in Figure 1.