Reduction of interleukin-10 production by B cells in intractable toxic epidermal necrolysis.

Several interleukin (IL)-10 producing B-cell subsets have been identified recently. However, few studies have examined the role of them in toxic epidermal necrolysis (TEN). We describe a 41-year-old woman with TEN who had B-cell lymphoma and a history of treatments including B-cell depletion therapy. Her re-epithelization was still ongoing after 7 months, despite treatments. To investigate her immune system, we compared cytokine and chemokine production from B cells and non-B cells isolated from the patient and another non-lymphoma TEN patient. IL-10 production from B cells decreased in the patient compared with the control TEN-only patient. Cytokine and chemokine levels from non-B cells involved in inflammation were elevated in the patient compared with the control patient. In conclusion, this study demonstrates that IL-10 from B cells as well as regulatory T cells is critical in the pathogenesis of TEN, and that B-cell dysfunction based on B-cell lymphoma and B-cell depletion therapy may be involved in the intractability of TEN.