Lack of response to laser comb in spontaneous and graft induced alopecia areata in C3H/HeJ mice

Alopecia areata (AA), the second most common form of hair loss in humans, is characterized by waxing and waning focal hair loss. Alopecic foci can expand to encompass the entire head (alopecia totalis) or body (alopecia universalis, AU). This cell mediated autoimmune disease is characterized histologically by the “swarm of bees”, CD4+ and CD8+ T cells, NK cells, and fewer numbers of other types of inflammatory cells in and around actively growing, anagen stage, hair follicles. Treatment of persistent, moderate to severe AA is palliative at best, often with a poor outcome (Harris et al., 2010). Investigation of AA in humans and nonhuman animal models, primarily C3H/HeJ mice (Sundberg et al., 1994), has provided new insights. Spontaneous AA in C3H/HeJ mice is sporadic, low frequency, and most commonly affects older female mice. Full thickness skin grafts of AA donor skin to young unaffected, immunocompetent, histocompatible recipients provides a highly reproducible model (McElwee et al., 1998) useful in preclinical trials (Sun et al., 2008).