Microsome, thyroid and DNA tests on patients with generalized vitiligo vulgaris, with or without Sutton's leukoderma, show a high positive rate without thyroid diseases. A small, but not negligible, amount of IgG and C3 deposits in the basement-membrane zone and keratinocytes, has been frequently seen in these diseases by immunohistology and immuno-electron microscopy. This evidence strongly suggests an autoimmune character for these diseases.

Mouseskin assays for collagen, determined as hydroxyproline, were carried out on a bleomycin-treated group and on untreated controls. Animals receiving bleomycin showed cutaneous collagen levels approximately 1.75 time higher than those exhibited by the untreated controls. With respect to the ratios of hydroxyproline in soluble collagen fraction to cutaneous total hydroxyproline content, the bleomycin-treated group displayed a roughly 50 per cent decrease in neutral salt soluble fraction and a slight diminution of the acid soluble fraction, as compared with the untreated controls. The findings indicate a significant increase in insoluble collagen content in the skin of mice receiving bleomycin.In an attempt to clarify the mechanismof collagenolysis by the anticancer antibiotic, cutaneous tissue specimens taken from animals treated with the antibiotic were grown in vitro, and crude collagenase preparations isolated from tissue cultures assayed radiologically, using *4C-glycine labelled collagen as the substrate.Lower cutaneous collagenolytic activity was observed in mice treated with bleomycin.Developedrecently as a unique anticancer drug virtually devoid of adverse side effects on the hematopoietic system, bleomycin1.2) is used at present primarily in the treatment of squamous cell carcinoma. Clinical as well as laboratory studies3.4) , however, have demonstrated the development of pulmonary fibrosis5) and changes in nail tissue65 as an occasional consequence of bleomycin administration, thus presenting some intricate problems in this anticancer chemotherapy. Meanwhile, there is as yet a dearth of information of particular note as to the mechanismof fibrotic response to bleomycin, with the exception of a report by Tezuka7) that bleomycin is capable of enhancing the activity of protocollagen proline hydroxylase which is involved in the biosynthesis ofcollagen.In view of this, the present study was undertaken to attempt an analysis of the fibrotic response of the skin of mice treated with bleomycin and, at the same time, to determine the course of biotransformation of the drug in cutaneous fibrosis in order to clarify the underlying mechanism. Materials and Methods(1) Bl eomyci n.Solutions of sterile bleomycin powder, supplied in vials containing the equivalents of 15 mg pure bleomycin base (Nippon-Kayaku Co., Ltd.), were used.(2) Laboratory animals.Animals used were 14-week-old male mice of the ICR strain with an average body weight of 25g.(3) Mouse skin assay for hydroxyproline following administration of bleomycin. 1) Drug administration: Bleomycin solution was administered to mice intraperitoneally in doses of lOmg/kg daily for 10 days and, on the 20th day after the conclusion of the 10-day dosing,

Sera of patients with various types of vitiligo have been found to contain circulating antibodies for the cytoplasmic components of human melanoma cell lines. This incidence is high, especially in generalized vitiligo vulgaris with or without Sutton's phenomenon. There is good correlation between the antibodies and positive microsome test, thyroid test, DNA test, as well as the effect of steroid ointment.