IMMUNOLOCALIZATION OF CYSTATIN A IN CONDYLOMATOUS AND DYSPLASTIC LESIONS OF THE HUMAN UTERINE CERVIX - CORRELATION WITH THE PRESENCE AND TYPE OF HUMAN PAPILLOMAVIRUS INFECTION

Cystatin A is the major cysteine proteinase inhibitor in human squamou s epithelia. We investigated the occurrence of cystatin A in normal, c ondylomatous, and dysplastic lesions of the cervix with or without hum an papillomavirus (HPV) infection. Cystatin A was detected by immunohi stochemistry and HPV infection by DNA hybridization techniques. In the normal uterine cervix, cystatin A was seen throughout the epithelium, except in the basal and parabasal cell layers. In condylomatous lesio ns, the staining intensity was similar to that in normal epithelium. I n low-grade cervical intraepithelial neoplasias (CINs), reduced staini ng was seen in the lower third of the epithelium; in high-grade CINs, a reduction in staining intensity was also seen in the middle and uppe r thirds. Cystatin A staining in epithelia and nuclei was negative in highly cellular and poorly differentiated CIN III. The cytoplasmic sta ining of cystatin A did not correlate with presence or type of HPV DNA . In the high-grade CINs infected with HPV types 16 and 18, however, c ystatin A staining was more often confined to the nuclear compartment.