CD4 and Alzheimer disease: As reported in a previous study [18], our analysis of lichenified eczema and eczematous erythema at positive APT sites in IgE-mediated AD demonstrated that, in addition to IL-13- CD3+ (CD4+) T cells (Th1 cells), small numbers of IL-13+ CD3+ (CD4+) T cells (i.e., Th2 cells) and IL-13+ CD3- lymphoid cells (presumably ILC2s) infiltrated some areas of the spongiotic epidermis.