Cytokine dynamics in FPIES during acute phase and stable status
To verify whether the elevation in serum IL-2 and IL-10 was specific to
the symptomatic period, we
compared the levels of the two cytokines in symptomatic and asymptomatic
stages in samples from FPIES patients (Figure 2 ). The results
showed that the serum levels of both cytokines were significantly higher
in the symptomatic than in the asymptomatic period (IL-2 median values:
218.7 pg/mL vs. <2.6 pg/mL, p = 0.002; IL-10 median
values: 31.8 pg/mL vs. 5.2 pg/mL, p < 0.001). Thus,
serum IL-2 and IL-10 returned to normal levels when the symptoms
disappeared.
Alterations in serum levels of IL-2 and IL-10 during OFC
Next, we evaluated the alterations of serum IL-2 and IL-10 levels
during the OFC test in patients No. 6 and No. 7 (Figures 3A and
3B ). The patients were challenged with causative foods and showed
vomiting 3 and 2 hours later, respectively. Notably, a marked increase
in the serum levels of IL-2 and IL-10 were observed immediately after
vomiting. In patient No. 5, both IL-2 and IL-10 levels were higher at
the time of vomiting than 6 hours after the beginning of the OFC
(Figure 3C ). In contrast, no elevation was observed in the two
cytokine levels before the OFC test and 24 hours after the beginning of
the OFC test. In contrast, this increase was not clearly observed in the
FPIES-resolved subject.