A novelty of our work is the simultaneous study of the constitutive subunit of the proteasome and TPP2 (both are intracellular markers associated with antigen turnover in the cytoplasm) together with the analysis of involucrin (cellular differentiation in the skin) and human beta defensin-2 (a marker of inflammation mainly in psoriasis) and their correlation with selected clinical parameters. This evidence concerns the gene TPP2 and psoriasis.