IGHE and Eczematoid dermatitis: For instance, Li et al. reported that Clostridium leptum induces proliferation of Treg cells (32); Rossi et al. reported that Faecalibacterium prausnitzii (a member of the Ruminococcaceae family) strongly induces IL-10 production (33); and Wu et al. reported that decreases in the proportion of the Ruminococcaceae family induce IgE-associated eczema in infants (34).