IL4 and selective IgA deficiency disease: In addition, when categorizing patients based on diagnosis, we observed significant changes in IFN-γ, IL-10, IL-15, and IL-4 levels in the SIgAD subgroup, whereas only changes in the levels of IFN-γ and TGF-β1 were observed in the CVID subgroup (see Supplementary Table S1a).