Systemically disseminated cutaneous T-cell lymphoma is generally resistant to chemotherapy and radiotherapy. We tested a treatment involving the extracorporeal photoactivation of biologically inert methoxsalen (8-methoxypsoralen) by ultraviolet A energy to a form that covalently cross-links DNA. After oral administration of methoxsalen, a lymphocyte-enriched blood fraction was exposed to ultraviolet A (1 to 2 J per square centimeter) and then returned to the patient. The combination of ultraviolet A and methoxsalen caused an 88 +/- 5 percent loss of viability of target lymphocytes, whereas the drug alone was inactive. Twenty-seven of 37 patients with otherwise resistant cutaneous T-cell lymphoma responded to the treatment, with an average 64 percent decrease in cutaneous involvement after 22 +/- 10 weeks (mean +/- SD). The responding group included 8 of 10 patients with lymph-node involvement, 24 of 29 with exfoliative erythroderma, and 20 of 28 whose disease was resistant to standard chemotherapy. Side effects that often occur with standard chemotherapy, such as bone marrow suppression, gastrointestinal erosions, and hair loss, did not occur. Although the mechanism of the beneficial effect is uncertain, an immune reaction to the infused damaged cells may have restricted the activity of the abnormal T cells. This preliminary study suggests that extracorporeal photochemotherapy is a promising treatment for widespread cutaneous T-cell lymphoma.
Several problems have frustrated the isolation of lamellar bodies (LB) from mammalian epidermis. We obtained pellets enriched in intact LB by utilizing the staphylococcal epidermolytic toxin to provide intact, outer epidermal sheets, by controlled homogenization in a cell disrupter, and by passage of homogenates through a graded series of nuclepore filters (Science 221:962, 1983). Such preparations contained more intact LB than did fractions prepared by a variety of differential or sucrose/metrizamide discontinuous centrifugation methods. Initial characterization of the enzymatic content of this fraction revealed it to be enriched in certain hydrolytic enzymes (acid phosphatase, carboxypeptidase, cathepsin B, acid lipase, sphingomyelinase, and phospholipase A), but strikingly depleted in all sulfatases, beta-glucuronidase, and the non-lysosomal protease, plasminogen activator. Thus, LB show some properties of lysosomes, although certain characteristic lysosomal enzymes are strikingly absent. Lamellar body fractions contained 2-3 times more lipid per unit weight than did homogenates, and were enriched in phospholipids, free sterols, and glycosphingolipids, but not in other neutral lipids or ceramides. In summary, whereas some of the enzymes in LB could participate in the metabolism of LB lipid precursors to hydrophobic barrier constituents, others may attack intercellular constituents, ultimately resulting in desquamation. The lipid profile of these organelles suggests that they deliver precursors of permeability barrier lipids to intercellular domains.
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