CD4+CD25+CD127^loFOXP3+ cell in food allergy: Does it predict anaphylaxis?

Food allergy (FA), hence the incidence of food anaphylaxis, is a public health problem that has increased in recent years. There are still no biomarkers for patients with FA to predict severe allergic reactions such as anaphylaxis.

There is limited information on whether regulatory T (Treg) cell levels are a biomarker that predicts clinical severity in cases presenting with FA, and which patients are at a greater risk for anaphylaxis.

A total of 70 children were included in the study: 25 who had IgE-mediated cow's milk protein allergy (CMPA) and presented with non-anaphylactic symptoms (FA/A-), 16 who had IgE-mediated CMPA and presented with anaphylaxis (FA/A+) (a total of 41 FA cases), and a control group consisting of 29 children without FA. The study was conducted by performing CD4+CD25+CD127^loFOXP3+ cell flow cytometric analysis during resting at least 2 weeks after the elimination diet to FA subjects.

When the FA group was compared with healthy control subjects, CD4+CD25+CD127_loFOXP3+ cell rates were found to be significantly lower in the FA group (p < 0.001). When the FA/A- and FA/A+ groups and the control group were compared in terms of CD4+CD25+CD127^loFOXP3+ cell ratios, they were significantly lower in the FA/A- and FA/A+ groups compared to the control group (p < 0.001).

Although there was no significant difference between the FA/A+ group and the FA/A- group in terms of CD4+CD25+CD127^loFOXP3+ cells, our study is important, as it is the first pediatric study we know to investigate whether CD4+CD25+CD127^loFOXP3+ cells in FA predict anaphylaxis.