In a mouse model of dermatitis in ears and back skins treated with oxazolone, the number of lymphatic vessels in ears and back skins increased after 21 days of inflammation (Huggenberger et al., 2010), and in an arthritis model using TNF‐transgenic mice the number of lymphatic vessels in the synovium increased after 14 days of inflammation (Zhang et al., 2007). This evidence concerns the gene TNF and dermatitis.