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.

No abstract

No abstract

No abstract

No abstract