Methods and compositions are provided for the creation and screening of non-human animal models having many of the histologic characteristics of human psoriasis. Immunocompromised host animals are injected with a purified population of CD45Rb positive cells, which are tolerant of the host major histocompatibility antigens, but are mismatched at one or more minor antigens. The injected cells are stimulated with a pro-inflammatory cytokine, e.g. IL-12, and a polyclonal activating agent. The injected animals develop a chronic skin disorder that includes histological features observed in human psoriasis, e.g. rete pegs, severe acanthosis and infiltration of Th1 cells into the dermis.