DNA synthesis in molluscum contagiosum nodules was investigated by autoradiography using 3H-thymidine. Scratch preparations of molluscum nodule stained with Giemsa showed that many cells contained reddish purple cytoplasmic inclusions. These inclusions were classified according to their size and characteristics into stages I, II and III. The inclusions in stages I and II had the same staining characteristics as “B” type inclusions of poxviruses. Inclusions in stage II appeared to be gradually transformed into stage III inclusions, which had a lobular structure and corresponded to the so-called molluscum bodies of Lipshiitz. The sites of cytoplasmic DNA synthesis corresponded exclusively with these inclusions. The responsible antigen was specifically localized to the molluscum bodies by the method of immunologic fluorescence microscopy. It was found by quantitative autoradiography that cells bearing inclusions did not show active nuclear DNA synthesis. Many cells with well-developed inclusions appeared to be degenerating. This suggests that virus-producing cells do not multiply but degenerate. Autoradiography of sections of the molluscum nodule showed that active nuclear DNA synthesis occurred only in the inclusion free-basal cells of the epidermis surrounding the molluscum foci. The host-virus interactions in molluscum contagiosum are similar to those in poxgroup viruses.
抄録全体を表示