The extraction and partial purification of the deoxycholate-soluble matrix protein from human plantar horny layer.

The electron-dense, amorphous matrix protein in human horny cells was extracted with deoxycholate. The deoxycholate-soluble material was partially purified by differential centrifugation and molecular sieve chromatography. Approximately 44% of the total protein was extracted into the 270,000 g supernatant fraction. Macroaggregates with histochemical characteristics indentical with those in situ keratohyalin granules were formed upon dialysing the 270,000 g supernatant fraction against redistilled water. Antibody was raised to the purified material of the initial peak from the Sepharose 6B column. The resulting antiserum yielded a single precipitin line when tested against the immunizing antigen. Electrophoresis in the presence of sodium dodecylsulfate showed this antigenic material to be heterogeneous. It was immunologically homogeneous when this antigenic material was examined by immuno-electrophoresis. Since the antibody was localized on the keratohyalin granules of human planter skin by indirect immunofluorescence, the partially purified, deoxycholate-soluble material from human plantar horny layers is considered to originate from keratohyalin granules. Amino acid analysis revealed a high content of glycine, glutamic acid and aspartic acid, and a low content of histidine and leucine.