Akira Kunisawa

Sarcoidosis induced by interferon therapy for chronic myelogenous leukaemia

A 31‐year‐old male was diagnosed as having chronic myelogenous leukaemia and has been treated with hydroxyurea and interferon‐α since February 1995. After 16 months, he complained of low‐grade fever and a cough. Bilateral hilar lymph node enlargement was detected on the chest X‐ray film and multiple subcutaneous erythematous nodules appeared. A skin biopsy revealed subcutaneous sarcoid granuloma. Two months after the cessation of interferon therapy, the subcutaneous nodules and the hilar lymph node enlargement resolved. It is possible that continuous interferon administration can promote granuloma formation in sarcoidosis by activating T cells and macrophages.

Direct Demonstration of the Productive Capability of Cytokines at the Single Cell Level in Lung Sarcoidosis Using Multicolor Cytometry

Background: Sarcoidosis is a chronic systemic disorder of unknown etiology characterized by noncaseating epithelioid cell granulomatous lesions, around which an increasing number of CD4+ T cells infiltrate. These CD4+ T cells may release interferon-γ (IFN-γ) and interleukin-2 (IL-2). These cytokines are considered to play an important role in pathogenesis of sarcoidosis. Methods: We employed a modification of Jung’s method using multicolor flow cytometry to assess the capability of single cells obtained from bronchoalveolar lavage (BAL) fluid to produce various cytokines. BAL CD4+ T cell production of IFN-γ, IL-2 and IL-4 after phorbol ester and ionomycin stimulation were studied. Results: The percentage of IFN-γ- and IL-2-producing CD4+ T cells was significantly higher in patients with sarcoidosis compared to healthy volunteers [84.7 ± 7.5 vs. 51.2 ± 14.8% (p < 0.005), and 75.3 ± 8.7 vs. 39.8 ±11.0% (p < 0.001), respectively]. No significant difference in the percentage of IL-4-producing CD4+ T cells was noted (1.2 ± 0.6 vs. 3.5 ± 2.6%; not significant), whereas the absolute number of IL-4-producing CD4+ T cells was significantly higher in patients with sarcoidosis compared to healthy volunteers (563.6 ± 330.2 vs. 50.9 ± 66.9/ml; p < 0.005). In the IL-4-producing CD4+ T cells, about 80% of cells concomitantly produced IFN-γ and more than 60% of cells also produced IL-2. Conclusion: We demonstrate that Th1-like-producing cells are predominant in the CD4+ as well as in the CD8+ T cell subset of patients with sarcoidosis. We for the first time demonstrated concomitant capabilities of BAL CD4+ T cells to produce Th1 and Th2 cytokines at the single cell level by multicolor flow cytometry.