AN IMMUNOHISTOCHEMICAL STUDY OF LYSOZYME IN THE SKIN OF PSORIATIC PATIENTS

The distribution of lysozyme was investigated in psoriatic skin lesion s, perilesional skin and in skin from healthy controls, using the immu noperoxidase techniques avidin-biotin complex and alkaline phosphatase -anti alkaline phosphatase. Lysozyme was identified in polymorphonucle ar leukocytes present in the Munro microabscesses and also occasionall y in other parts of the skin, as shown by very strong cytoplasmic stai ning Stratum corneum, stratum granulosum and stratum spinosum were wea kly stained. In some cases positive staining along the dermal collagen bundles was demonstrated and is most likely to be related to the numb er of inflammatory cells in the papillary dermis. Psoriatic skin lesio ns stained significantly stronger for lysozyme than did perilesional s kin (p < 0.0001), whereas skin from healthy controls stained weakly po sitive or was lysozyme negative. Lysozyme may be of some importance in the psoriatic disease process. By comparison the alkaline phosphatase -antialkaline phosphatase was found to be the most specific of the two techniques.