In a recent study in our mouse allergy model, inhalation of ultrafine carbon particles prior to OVA challenge caused most significant changes in Clara cell protein CC16 in BALF and serum, BALFs total protein and TNF-α expression in lung homogenates and the strongest morphological alterations of Clara cells and goblet cell metaplasia in sensitized mice compared to non-sensitized mice [38]. Here, TNF is linked to allergic disease.