Comparison of swelling between the oral mucosa and footpad of Ni-induced allergic mice.

The swelling of ACM and F-ACD mice at 1, 2, 3, and 7 days after the first and second challenges. At day 0 and day 14 after sensitization, the challenge was performed in ACM and F-ACD mice. Swelling at day 1 after the first challenge was significantly increased in ACM mice compared with F-ACD mice. Swelling from 1 to 7 days after the second challenge was significantly increased in F-ACD mice compared with ACM mice. Bars and error bars indicate the mean plus standard deviation. Statistical significance was tested by the Mann–Whitney U-test (** p p < 0.0001).