Interferon kappa

Interferon-kappa (IFN-κ) is a member of the type I interferon family and plays a role in the body's immune response. IFN-κ is mainly expressed in keratinocytes and in some other immune cells. Its expression can be induced by various stimuli, such as viral infections or other immunostimulatory factors.

IFN-κ acts via the interferon-alpha/beta receptor (IFNAR), which is present on many cell types. Binding of IFN-κ to this receptor activates intracellular signaling pathways that lead to the expression of interferon-stimulable genes (ISGs). Like other type I interferons, IFN-κ has antiviral properties and can inhibit viral replication in infected cells. Furthermore, this interferon also has immunomodulatory properties that can influence the activity of various immune cells, including T cells and natural killer cells (NK cells).

Due to its expression in keratinocytes, IFN-κ plays an important role in skin immunity and may play a role in the defense against skin infections and in the regulation of skin inflammation.

IFN-κ protein expression in the epidermis is very low in normal skin. However, it is significantly increased in the suprabasal layers of epidermal keratinocytes in psoriatic skin lesions. In addition, IFN-κ was detected in sera from psoriasis patients, but not in sera from normal individuals and atopic dermatitis (Li Y et al. 2019).

In wound healing, the type I IFN signaling pathway is important for regulating the inflammatory response after skin injury. Ifnk expression is upregulated in keratinocytes early after injury and is essential for normal tissue repair. In contrast, under diabetic conditions, IFN-κ in wound keratinocytes is reduced and early inflammation is impaired. (Wolf SJ et al. 2022)

1. Li Y et al. (2019) Interferon Kappa Is Up-Regulated in Psoriasis and It Up-Regulates Psoriasis-Associated Cytokines in vivo. Clin Cosmet Investig Dermatol12:865-873.
2. Wolf SJ et al. (2022) IFN-κ is critical for normal wound repair and is decreased in diabetic wounds. JCI Insight 7:e152765.