#keratinocytes

• Acantholysis — A histological pathological process characterized by the loss of intercellular cohesion between keratinocytes in the stratum spinosum of the epidermis, caused by the destruction or dysfunction of desmosomes (cellular junction structures). This biochemical and immunological phenomenon leads to the separation of epithelial cells, formation of clefts, and subsequent development of intraepidermal vesicles or bullae, serving as the definitive microscopic hallmark for severe autoimmune diseases such as pemphigus vulgaris.
• Acanthoma — A benign cutaneous tumor formation characterized by the hyperplastic proliferation of keratinocytes within the stratum spinosum of the epidermis (acanthosis). This well-circumscribed lesion can manifest in various clinical and histological forms, the most notable being clear cell acanthoma (Degos) and acanthoma fissuratum, requiring microscopic differential diagnosis to exclude epidermal malignancies.