Clinical and histologic correlations were performed on five adult patients with verrucae vulgaris lesions and on four normal adult volunteers without verrucae after induction of irritant contact dermatitis and subsequent allergic contact immune response to 1-nitro-2,4-dichlorobenzene (DNCB). Four of the five patients with warts and all of the control patients developed normal delayed cutaneous hypersensitivity (DCH) reactions. The four patients with verrucae vulgaris, with induced DCH responses, had disappearance of the warts after topical challenge by DNCB. After several weeks, two of these patients experienced complete disappearance of all nontreated warts, as well.
Greenberg JH, Smith TL, Katz RM. Verrucae Vulgaris RejectionA Preliminary Study of Contact Dermatitis and Cellular Immunity Response. Arch Dermatol. 1973;107(4):580-582. doi:10.1001/archderm.1973.01620190056013