LRIG1 expression during homeostasis and skin wound healing in mice

Leucine-rich repeats and immunoglobulin-like domains (LRIG)-1 belong to the family of proteins known to be expressed in skin. Ablation of LRIG1 in mice results in epidermal hyperplasia and its aberrant expression levels have been reported in pathological conditions such as psoriasis, thus evident of an indispensible role of LRIG1 in maintaining epidermal homeostasis. In order to gain insight into the homeostatic expression of LRIG1 and in various stages of cutaneous wound healing, LRIG1 expression was immunohistochemically analyzed in full thickness skin wounds in mice. The full thickness skin wounds were established on the dorsal back of Balb/c mice (n=6). LRIG1 expression at various post wounding days (1, 2, 3, 6 and 14) was determined through Immunohistochemical analysis (IHC) of the murine skin sections. The injury caused a sharp decline in LRIG1 expression in the basal epidermal cells and appendages surrounding the wound which correlates with the re-epithelialization phase of healing. LRIG1 expression remained down regulated during most of the wound healing stages. LRIG1+ cells were found to re-populate the neo-epidermis on day 14, suggesting an important homeostatic role of LRIG1 in skin.