NLRP12 and allergic disease: Contact allergens, such as p-phenylenediamine (PPD) and 2,4-dinitrochlorobenzene (DNCB), increased the expression of Blimp-1 and IL-18, which are critical players in allergic diseases [132], but decrease NLRP12 expression in human keratinocytes, NCTC 2544 cells [133].