Epidermodysplasia Verruciformis Lesions Research Articles

Characterization of two types of human papillomaviruses in lesions of epidermodysplasia verruciformis

Human papillomaviruses (HPVs) found in lesions of 11 patients suffering from epidermodysplasia verruciformis were compared to HPV type 1 (HPV-1) and HPV type 2 (HPV-2) previously characterized in plantar and common warts, respectively. Complementary RNAs (cRNAs) to HPV-1, HPV-2, and viruses obtained from two patients with epidermodysplasia verruciformis (J.D. HPV and J.K. HPV) were used in cRNA.DNA filter hybridization experiments. No sequence homology was detected between HPV-1 or HPV-2 DNAs and DNAs obtained from the 11 epidermodysplasia verruciformis HPV isolates. Furthermore, with J.D. and J.K. HPV cRNAs, epidermodysplasia verruciformis HPV DNAs fell into two groups showing little, if any, sequence homology. A lower extent of annealing was observed for the DNAs of some isolates showing a genetic heterogeneity within each of the two groups. Almost no antigenic crossreaction was detected by immunodiffusion and indirect immunofluorescence tests, either between epidermodysplasia verruciformis HPVs and HPV-1 or HPV-2 or between J.D. and J.K. HPVs. Viruses belonging to the same group have common antigenic properties, but antigenic differences were observed when two of the viruses sharing only partial DNA sequence homology were compared. Viruses related to J.D. HPV were preferentially associated with flat wart-like lesions of epidermodysplasia verruciformis and were further found in the lesions of five patients bearing multiple flat warts. Viruses related to J.K. HPV were found in morphologically distinct lesions (red spots) present in some patients with epidermodysplasia verruciformis. Thus, we propose to distinguish two other types of HPVs designated provisionally as HPV type 3 (HPV-3) and HPV type 4 (HPV-4), with J.D. and J.K. HPVs as prototypes, respectively. Malignant conversion of some epidermodysplasia verruciformis lesions is more frequently associated with HPV-4 than with HPV-3 infection.

The Virus Of Epidermodysplasia Verruciformis: Electron Microscopic And Fluorescent Antibody Studies

Five cases of epidermodysplasia verruciformis were studied for viral particles and antigens. In all benign lesions tested, viral particles and antigens were observed by electron microscopy of ultrathin sections and/or tissue extracts and by fluorescent antibody staining with an antiserum against human wart virus. Both viral particles and antigens were observed in the cells of the stratum granulosum and the stratum corneum and not in those of deeper layers. Viral particles and antigens were observed in nuclei. Viral particles resembled morphologically the virus of common human warts. In two, one on the forehead and the other on the inner aspect of the upper thigh, of six lesions showing the histology of early malignancy, viral particles were observed by electron microscopy of ultrathin sections and/or tissue extracts. Four advanced malignant lesions, two primary ulcerated squamous cell carcinomas and two recurrent carcinomas, were similarly studied. In none of them, were viral particles or antigens detected. These results suggest that (1) the virus of epidermodysplasia verruciformis is related with that of common human warts both morphologically and antigenically, (2) at least some of the virus-induced lesions of epidermodysplasia verruciformis become malignant, and (3) when the lesions are completely replaced with malignant cells, neither viral particles nor antigens are recognizable in them.

Ultrastructure of Clear Cells in Human Viral Warts

In an attempt to determine the viral content and to observe the morphological features of clear cells in human warts of various clinical types, 17 lesions were studied with the electron microscope and 26 in thick sections. Plantar warts were, by far, the richest in viral particles, which are often found in crystalline arrangement. Morphologically, three groups observed in thick sections were also discovered with the electron microscope. In flat warts, poor in keratohyaline, the vacuolating process was total and massive, with abundant viral particles in the nucleus; two flat warts were taken from immunosuppressed patients and their appearance was quite similar to epidermodysplasia verruciformis lesions. In common warts, poorer in virus particles but rich in keratohyaline, vacuolization was often not complete. In plantar warts, characterized by their peculiar wealth in viral particles sometimes invading the cytoplasm, the production of keratohyaline was tremendous and the vacuolization, although often complete, was, however, not massive. Thus it seems that keratohyaline production is related to viral production but hampered by the vacuolating process and differing according to the ultrastructure of the three types of warts. It is suggested that the oncogenic potential of a wart (papilloma) may be related to decrease in keratohyaline production, i.e. cell maturation, and increase in vacuolization.