Levels of proelafin peptides in the sera of the patients with generalized pustular psoriasis and pustulosis palmoplantaris.

The levels of proelafin peptides in the sera of patients with pustulosis palmoplantaris, a unique type of localized pustular psoriasis, and generalized pustular psoriasis were determined by competitive enzyme-linked immunosorbent assays using antibodies against synthetic proelafin polypeptides corresponding to the elastase inhibitor (elafin) and transglutaminase substrate domains. The sera of patients with pustulosis palmoplantaris (9 cases) exhibited a normal range of proelafin peptide levels. The sera of patients with generalized pustular psoriasis (3 cases) showed high titres of proelafin peptide. There were no large differences in the titres between the 2 antibodies. The antibodies for 2 different domains of proelafin showed a similar immunoreactivity for the non-pustular region of the epidermis in all pustulosis palmoplantaris tested. The results indicate that serum proelafin peptides in pustular psoriasis may depend on the extent of the involved area, and that proelafin peptide level in pustulosis palmoplantaris remains normal despite enhanced local expression in the lesional skin. Since the skin lesions of patients with pustulosis palmoplantaris are limited to the palms and soles, enhanced expression of proelafin in the lesional skin may not lead to elevation of proelafin peptides in the serum.