The molecular puzzle of autoinflammatory skin diseases-a review of chosen conditions.

The skin is one of the largest organs in humans and is formed by a layer (termed the epidermis) that enables the body to interact with the environment and protects it from various harmful agents. The epidermis includes a physical, biochemical, and adaptive immune barrier. The immune system in the human body is responsible for protecting organisms from potentially infectious microorganisms, allergens, and toxins, maintaining homeostasis, controlling inflammation processes, and tissue repair. Autoimmune and autoinflammatory diseases are of the immune system manifesting as aberrations in adaptive and innate immunity that lead to an inflammatory state and self-attack damage, also in the skin. The commonness of cutaneous autoinflammations has increased over the past decades, and the occurrence of the disease can have a crucial impact on a patient's quality of life due to their visible nature, discomfort caused by somatic symptoms, and emotional and social challenges. In this review, we summarize the current knowledge of four common autoinflammatory skin diseases-vitiligo, alopecia areata, systemic lupus erythematosus, and psoriasis-with particular emphasis on their molecular background, including the role of genetic susceptibility, epigenetic regulation, and immunological pathways.