Koebnerisin (S100A7A) was first identified upregulated in inflammation-prone psoriatic skin, suggesting involvement in the lesional phenotype of the disease,[4] Koebner phenomenon.

Today, the protein is of further interest because of its role in antimicrobial defence, innate immunity, epidermal cell maturation and epithelial tumorigenesis.

[11] Koebnerisin (S100A7A) functions as an antimicrobial peptide (AMP) reducing survival of E. coli and was strongly regulated by several bacterial components, such as Pseudomonas aeruginosa and Staphylococcus aureus.

Koebnerisin (S100A7A) maps to the S100 gene cluster within the epidermal differentiation complex (EDC, chromosome 1q21) and reveals an unusual genomic organization compared to other S100 members.

Koebnerisin (S100A7A) has lately evolved by gene duplications within the Epidermal Differentiation Complex (EDC, chromosome 1q21) during primate evolution forming a novel S100 subfamily together with Psoriasin (S100A7).