Fig. 3.

Immune dysfunction in atopic dermatitis. Genetic predispositions, such as FLG mutations, can weaken the physical strength of the epidermal barrier. In addition, colonization by S. aureus also causes inflammation and excoriation, worsening barrier function. With loss of barrier function, aeroallergens are able to interact with dendritic cells, and via antigen presentation, activate naïve T cells. The presence of TSLP enables naïve T cells to differentiate and expand as Th2 cells, which secrete IL-4 and IL-13. These cytokines are important in class switching of B cells to secrete IgE as well as their ability to diminish the secretion of antimicrobial peptides